Taint: invert the taint-check implementation control #define
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38THE EXIM FAQ
39------------
40
41This is the FAQ for the Exim Mail Transfer Agent. Many thanks to the many
42people who provided the original information. This file would be amazingly
43cluttered if I tried to list them all. Suggestions for corrections,
44improvements, and additions are always welcome.
45
8e26e4bf 46This version of the FAQ applies to Exim 4.43 and later releases.
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47
48References of the form Cnnn, Fnnn, Lnnn, and Snnn are to the sample
49configuration, filter, \^^local_scan()^^\, and ``useful script'' files. These
50are hyperlinked from the HTML version of this FAQ. They can also be found in
51the separately distributed directory called \(config.samples)\. The primary
52location is
53
54\?ftp://ftp.csx.cam.ac.uk/pub/software/email/exim/exim4/config.samples.tar.gz?\
55\?ftp://ftp.csx.cam.ac.uk/pub/software/email/exim/exim4/config.samples.tar.bz2?\
56
57There are brief descriptions of these files at the end of this document.
58
59Philip Hazel
8e26e4bf 60Last update: 14-October-2004
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61
62
63The FAQ is divided into the following sections:
64
65 0. General Debugging
66 1. Building and Installing
67 2. Routing in general
68 3. Routing to remote hosts
69 4. Routing for local delivery
70 5. Filtering
71 6. Delivery
72 7. Policy controls
73 8. Rewriting addresses
74 9. Headers
75 10. Performance
76 11. Majordomo
77 12. Fetchmail
78 13. Perl
79 14. Dial-up and ISDN
80 15. UUCP
81 16. Modifying message bodies
82 17. Encryption (TLS/SSL)
83 20. Millennium
84 50. Miscellaneous
85 91. Mac OS X
86 92. FreeBSD
87 93. HP-UX
88 94. BSDI
89 95. IRIX
90 96. Linux
5e0b134b 91 97. Sun systems
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92 98. Configuration cookbook
93 99. List of sample configurations
94
95
96
970. GENERAL DEBUGGING
98
99Q0001: Exim is crashing. What is wrong?
100
101A0001: Exim should never crash. The author is always keen to know about
102 crashes, so that they can be diagnosed and fixed. However, before you
103 start sending me email, please check that you are running the latest
104 release of Exim, in case the problem has already been fixed. The
105 techniques described below can also be useful in trying to pin down
106 exactly which circumstances caused the crash and what Exim was trying to
8e26e4bf 107 do at the time. If the crash is reproducible (by a particular message,
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108 say) keep a copy of that message.
109
110
111Q0002: Exim is not working. What is wrong? How can I check what it is doing?
112
113A0002: Exactly how is it not working? Check the more specific questions in the
114 other sections of this FAQ. Some general techniques for debugging are:
115
116 (1) Look for information in Exim's log files. These are in the \(log)\
117 directory in Exim's spool directory, unless you have configured a
118 different path for them. Serious operational problems are reported
119 in paniclog.
120
121 (2) If the problem involves the delivery of one or more messages, try
122 forcing a delivery with the \-M-\ option and also set the \-d-\
123 option, to cause Exim to output debugging information. For example:
124
125==> exim -d -M 0z6CXU-0005RR-00
126
127 The output is written to the standard error stream. You need to have
128 admin privileges to use \-M-\ and \-d-\.
129
130 (3) If the problem involves incoming SMTP mail, try using the \-bh-\
131 option to simulate an incoming connection from a specific host,
132 for example:
133
134==> exim -bh 10.9.8.7
135
136 This goes through the motions of an SMTP session, without actually
137 accepting a message. Information about various policy checks is
138 output. You will need to know how to pretend to be an SMTP client.
139
140 (4) If the problem involves lack of recognition or incorrect handling
141 of local addresses, try using the \-bt-\ option with debugging turned
142 on, to see how Exim is handling the address. For example,
143
144==> exim -d -bt z6abc
145
146 shows you how it would handle the local part \"z6abc"\.
147
148
149Q0003: What does the error \*Child process of address_pipe transport returned
8e26e4bf 150 127 from command xxx*\ mean?
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151
152A0003: It means that when a transport called \%address_pipe%\ was run to pass an
153 email message by means of a pipe to another process running the command
8e26e4bf 154 xxx, the return code from that command was 127, which indicates some kind
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155 of error (the success return code is 0).
156
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157 The most common meaning of exit code 127 is that when Exim tried to run
158 the command \(xxx)\, it failed. One cause of this might be incorrect
159 permissions on the file containing the command. See also Q0026.
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160
161
162Q0004: My virtual domain setup isn't working. How can I debug it?
163
164A0004: You can use an exim command with \-d-\ to get it to show you how it is
165 processing addresses. You don't actually need to send a message; use the
166 \-bt-\ option like this:
167
168==> exim -d -bt localpart@virtualhost
169
170 This will show you which routers it is using. If the problem appears
171 to be with the expansion of an option setting, you can use the
172 \debug_print\ option on a router to get Exim to output the expanded
173 string values as it goes along.
174
175
176Q0005: Why is Exim not rejecting incoming messages addressed to non-existent
177 users at SMTP time?
178
179A0005: This is controlled by the ACL that is run for each incoming RCPT
180 command. It is defined by the \acl_smtp_rcpt\ option. You can check this
181 part of your configuration by using the \-bh-\ option to run a simulated
182 SMTP session, during which Exim will tell you what things it is
183 checking.
184
185
186Q0006: I've put an entry for \"*.my.domain"\ in a DBM lookup file, but it isn't
187 getting recognized.
188
189A0006: You need to request ``partial matching'' by setting the search type to
190 \partial-dbm\ in order for this to work.
191
192
193Q0007: I've put the entry \"*@domain.com"\ in a lookup database, but it isn't
194 working. The expansion I'm using is:
195
196==> ${lookup{${lc:$sender_address}}dbm{/the/file} ...
197
198A0007: As no sender address will ever be //*@domain.com// this will indeed have
199 no effect as it stands. You need to tell Exim that you want it to look
200 for defaults after the normal lookup has failed. In this case, change the
201 search type from \"dbm"\ to \"dbm*@"\. See the section on \*Default values in
202 single-key lookups*\ in the chapter entitled \*File and database
203 lookups*\ in the Exim manual.
204
205
206Q0008: If I run \"./exim -d -bt user@domain"\ all seems well, but when I send
207 a message from my User Agent, it does not arrive at its destination.
208
209A0008: Try sending a message directly to Exim by typing this:
210
211==> exim -v user@domain
212 <some message, could be empty>
213 .
214
215 If the message gets delivered to a remote host, but never arrives at its
216 final destination, then the problem is at the remote host. If, however,
217 the message gets through correctly, then the problem may be between your
218 User Agent and Exim. Try setting Exim's \log_selector\ option to include
219 \"+arguments"\, to see with which arguments the UA is calling Exim.
220
221
222Q0009: What does \*no immediate delivery: too many messages received in one SMTP
223 connection*\ mean?
224
225A0009: An SMTP client may send any number of messages down a single SMTP
226 connection to a server. Initially, an Exim server starts up a delivery
227 process as soon as a message is received. However, in order not to start
228 up too many processes when lots of messages are arriving (typically
229 after a period of downtime), it stops doing immediate delivery after a
230 certain number of messages have arrived down the same connection. The
231 threshold is set by \smtp_accept_queue_per_connection\, and the default
232 value is 10. On large systems, the value should be increased. If you are
233 running a dial-in host and expecting to get all your mail down a single
234 SMTP connection, then you can disable the limit altogether by setting
235 the value to zero.
236
237
238Q0010: Exim puts \*for \[address]\*\ in the ::Received:: headers of some, but not all,
239 messages. Is this a bug?
240
241A0010: No. It is deliberate. Exim inserts a ``for'' phrase only if the incoming
242 message has precisely one recipient. If there is more than one
243 recipient, nothing is inserted. The reason for this is that not all
244 recipients appear in the ::To:: or ::Cc:: headers, and it is considered a
245 breach of privacy to expose such recipients to the others. A common
246 case is when a message has come from a mailing list.
247
248
249Q0011: Instead of \^exim_dbmbuild^\, I'm using a homegrown program to build DBM
250 (or cdb) files, but Exim doesn't seem to be able to use them.
251
252A0011: Exim expects there to be a binary zero value on the end of each key used
253 in a DBM file if you use the \"dbm"\ lookup type, but not for the \"dbmnz"\
254 lookup type or for the keys of a cdb file. Check that you haven't
255 slipped up in this regard.
256
257
258Q0012: Exim is unable to route to any remote domains. It doesn't seen to be
259 able to access the DNS.
260
261A0012: Try running \"exim -d+resolver -bt \[remote address]\"\. The \-d-\
262 options turns on debugging output, and the addition of \"+resolver"\
263 will make it show the resolver queries it is building and the results of
264 its DNS queries. If it appears unable to contact any name servers, check
265 the contents and permissions of \(/etc/resolv.conf)\.
266
267
268Q0013: What does the error message \*transport system_aliases: cannot find
269 transport driver "redirect" in line 92*\ mean?
270
271A0013: \%redirect%\ is a router, not a transport. You have put a configuration
272 for a router into the transports section of the configuration file.
273
274
275Q0014: Exim is timing out after receiving and responding to the DATA command
276 from one particular host, and yet the client host also claims to be
277 timing out. This seems to affect only certain messages.
278
279A0014: This kind of problem can have many different causes.
280
281 (1) This problem has been seen with a network that was dropping all
282 packets over a certain size, which mean that the first part of the SMTP
283 transaction worked, but when the body of a large message started
284 flowing, the main data bits never got through the network. See also
285 Q0017.
286
287 (2) This can also happen if a host has a broken TCP stack and won't
288 reassemble fragmented datagrams.
289
290 (3) A very few ISDN lines have been seen which failed when certain data
291 patterns were sent through them, and replacing the routers at both end
292 of the link did not fix things. One of them was triggered by more than 4
293 X's in a row in the data.
294
295
296Q0015: What does the message \*Socket bind() to port 25 for address (any)
297 failed: address already in use*\ mean?
298
299A0015: You are trying to run an Exim daemon when there is one already running -
300 or maybe some other MTA is running, or perhaps you have an SMTP line in
301 \(/etc/inetd.conf)\ which is causing \(inetd)\ to listen on port 25.
302
303
304Q0016: I've set \"verify = header_syntax"\ in my ACL, but this causes Exim to
305 complain about header lines like \"To: Work: Jim <jims@email>,
306 Home: Bob <bobs@email>"\ which look all right to me. Is this a bug?
307
308A0016: No. Header lines such as ::From::, ::To::, etc., which contain addresses, are
309 structured, and have to be in a specific format which is defined in RFC
310 2822. Unquoted colons are not allowed in the ``phrase'' part of an email
311 address (they are OK in other headers such as ::Subject::). The correct
312 form for that header is
313
314==> To: "Work: Jim" <jims@email>, "Home: Bob" <bobs@email>
315
316 You will sometimes see unquoted colons in ::To:: and ::Cc:: headers, but only
317 in connection with name lists (called ``groups''), for example:
318
319==> To: My friends: X <x@y.x>, Y <y@w.z>;,
320 My enemies: A <a@b.c>, B <b@c.d>;
321
322 Each list must be terminated by a semicolon, as shown.
323
324
325Q0017: Whenever Exim tries to deliver a specific message to a particular
326 server, it fails, giving the error \*Remote end closed connection after
327 data*\ or \*Broken pipe*\ or a timeout. What's going on?
328
329A0017: \*Broken pipe*\ is the error you get on some OS when the remote host just
330 drops the connection. The alternative is \*connection reset by peer*\.
331 There are many potential causes. Here are some of them (see also Q0068):
332
333 (1) There are some firewalls that fall over on binary zero characters
334 in email. Have a look, e.g. with \"hexdump -c mymail | tail"\ to see if
335 your mail contains any binary zero characters.
336
337 (2) There are broken SMTP servers around that just drop the connection
338 after the data has been sent if they don't like the message for some
339 reason (e.g. it is too big) instead of sending a 5xx error code. Have
340 you tried sending a small message to the same address?
341
342 It has been reported that some releases of Novell servers running NIMS
343 are unable to handle lines longer than 1024 characters, and just close
344 the connection. This is an example of this behaviour.
345
346 (3) If the problem occurs right at the start of the mail, then it could
347 be a network problem with mishandling of large packets. Many emails are
348 small and thus appear to propagate correctly, but big emails will
349 generate big IP datagrams.
350
351 There have been problems when something in the middle of the network
352 mishandles large packets due to IP tunnelling. In a tunnelled link, your
353 IP datagrams gets wrapped in a larger datagram and sent over a network.
354 This is how virtual private networks (VPNs), and some ISP transit
355 circuits work. Since the datagrams going over the tunnel require a
356 larger packet size, the tunnel needs a bigger maximum transfer unit
357 (MTU) in the network handling the tunnelled packets. However, MTUs
358 are often fixed, so the tunnel will try to fragment the packets.
359
360 If the systems outside the tunnel are using path MTU discovery, (most
361 Sun Sparc Solaris machines do by default), and set the DF (don't
362 fragment) bit because they don't send packets larger than their \(local)\
363 MTU, then ICMP control messages will be sent by the routers at the
364 ends of the tunnel to tell them to reduce their MTU, since the tunnel
365 can't fragment the data, and has to throw it away. If this mechanism
366 stops working, e.g. a firewall blocks ICMP, then your host never
367 knows it has hit the maximum path MTU, but it has received no ACK on
368 the packet either, so it continues to resend the same packet and the
369 connection stalls, eventually timing out.
370
371 You can test the link using pings of large packets and see what works:
372
f0884f39 373==> ping -s host 2048
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374
375 Try reducing the MTU on the sending host:
376
f0884f39 377==> ifconfig le0 mtu 1300
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378
379 Alternatively, you can reduce the size of the buffer Exim uses for SMTP
380 output by putting something like
381
382==> DELIVER_OUT_BUFFER_SIZE=512
383
384 in your \(Local/Makefile)\ and rebuilding Exim (the default is 8192).
385 While this should not in principle have any effect on the size of
386 packets sent, in practice it does seem to have an effect on some OS.
387
388 You can also try disabling path MTU discovery on the sending host. On
389 Linux, try:
390
391==> echo 1 >/proc/sys/net/ipv4/ip_no_pmtu_disc
392
393 For a general discussion and information about other operating systems, see
394 \?http://www.netheaven.com/pmtu.html?\. If disabling path MTU discovery
395 fixes the problem, try to find the broken or misconfigured
396 router/firewall that swallows the ICMP-unreachable packets. Increasing
397 timeouts on the receiving host will not work around the problem.
398
399
400Q0018: Why do messages not get delivered down the same connection when I do
401 something like: \"exim -v -R @aol.com"\? For other domains, I do this and
402 I see the appropriate \*waiting for passed connections to get used*\
403 messages.
404
405A0018: Recall that Exim does not keep separate queues for each domain, but
406 operates in a distributed fashion. Messages get into its `waiting for
407 host x' hints database only when a delivery has been tried, and has had
408 a temporary error. Here are some possibilities:
409
410 (1) The messages to \(aol.com)\ got put in your queue, but no previous
aded2255 411 delivery attempt occurred before you did the \-R-\. This might have been
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412 because of your settings of \queue_only_load\, \smtp_accept_queue\, or any
413 other option that caused no immediate delivery attempt on arrival. If
414 this is the case, you can try using \-qqR-\ instead of \-R-\.
415
416 (2) You have set \connection_max_messages\ on the smtp transport, and
417 that limit was reached. This would show as a sequence of messages
418 down one connection, then another sequence down a new connection, etc.
419
420 (3) Exim tried to pass on the SMTP connection to another message, but
421 that message was in the process of being delivered to \(aol.com)\ by some
422 other process (typically, a normal queue runner). This will break the
423 sequence, though the other delivery should pass its connection on to
424 other messages if there are any.
425
426 (4) The folk at \(aol.com)\ changed the MX records so the host names have
427 changed - or a new host has been added. I don't know how likely this is.
428
429 (5) Exim is not performing as it should in this regard, for some reason.
430 Next time you have mail queued up for \(aol.com)\, try running
431
432==> exim_dumpdb /var/spool/exim wait-remote_smtp
433
434 to see if those messages are listed among those waiting for the relevant
435 \(aol.com)\ hosts.
436
437
438Q0019: There seems to be a problem in the string expansion code: it doesn't
439 recognize references to headers such as \"${h_to}"\.
440
441A0019: The only valid syntax for header references is (for example) \"$h_to:"\
442 because header names are permitted by RFC 2822 to contain a very wide
443 range of characters. A colon (or white space) is required as the
444 terminator.
445
446
447Q0020: Why do connections to my machine's SMTP port take a long time to respond
448 with the banner, when connections to other ports respond instantly? The
449 delay is sometimes as long as 30 seconds.
450
451A0020: These kinds of delay are usually caused by some kind of network problem
452 that affects outgoing calls made by Exim at the start of an incoming
453 connection. Configuration options that cause outgoing calls are:
454
455 (1) \rfc1413_hosts\ and \rfc1413_query_timeout\ (for \*ident*\ calls).
456 Firewalls sometimes block ident connections so that they time out,
457 instead of refusing them immediately. This can cause this problem.
458 See Q5023 for a discussion of the usefulness of \*ident*\.
459
460 (2) The \host_lookup\ option, the \host_reject_connection\ option, or a
461 condition in the ACL that runs at connection time requires the
462 remote host's name to be looked up from its IP address. Sometimes
463 these DNS lookups time out. You can get this effect with ACL
464 statements like this:
465
466==> deny hosts = *.x.example
467
468 If at all possible, you should use IP addresses instead of host
9c2b45c9 469 names in blocking lists in order to avoid this problem.
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470
471 You can use the \-bh-\ option to get more information about what is
472 happening at the start of a connection. However, note that the \-bh-\
473 option does not provide a complete simulation. In particular, no
474 \*ident*\ checks are done, so it won't show up a delay problem that is
475 related to (1) above.
476
477
478Q0021: What does \*failed to create child process to send failure message*\ mean?
479 This is a busy mail server with \smtp_accept_max\ set to 500, but this
480 problem started to occur at about 300 incoming connections.
481
482A0021: Some message delivery failed, and when Exim wanted to send a bounce
483 message, it was unable to create a process in which to do so. Probably
484 the limit on the maximum number of simultaneously active processes has
485 been reached. Most OS have some means of increasing this limit, and in
486 some operating systems there is also a limit per uid which can be
487 varied.
488
489
490Q0022: What does \*No transport set by system filter*\ in a log line mean?
491
492A0022: Your system filter contains a \"pipe"\ or \"save"\ or \"mail"\ command,
493 but you have not set the corresponding option which specifies which
494 transport is to be used. You need to set whichever of
495 \system_filter_pipe_transport\, \system_filter_file_transport\ or
496 \system_filter_reply_transport\ is relevant.
497
498
499Q0023: Why is Exim refusing to relay, saying \*failed to find host name from IP
500 address*\ when I have the sender's IP address in an ACL condition? My
501 configuration contains this ACL statement:
502
503==> accept hosts = lsearch;/etc/mail/relaydomains:192.168.96.0/24
504
505A0023: When checking a host list, the items are tested in left-to-right
506 order. The first item in your list is a lookup on the incoming host's
507 name, so Exim has to determine the name from the incoming IP address in
508 order to perform the test. If it can't find the host name, it can't do
509 the check, so it gives up. You would have discovered what was going
510 on if you had run a test such as
511
512==> exim -bh 192.168.96.131
513
514 The solution is to put all explicit IP addresses first in the list.
515 Alternatively, you can split the ACL statement into two like this:
516
517==> accept hosts = lsearch;/etc/mail/relaydomains
518 accept hosts = 192.168.96.0/24
519
520 If the host lookup fails, the first \"accept"\ fails, but then the
521 second one is considered.
522
523
524Q0024: When I run \"exim -bd -q10m"\ I get \*PANIC LOG: exec of exim -q failed*\.
525
526A0024: This probably means that Exim doesn't know its own path so it can't
527 re-exec itself to do the first queue run. Check the output of
528
529==> exim -bP exim_path
530
531
532Q0025: I can't seem to get a pipe command to run when I include a \"${if"\
533 expansion in it. This fails:
534
535==> command = perl -T /usr/local/rt/bin/rtmux.pl \
536 rt-mailgate helpdesk \
537 ${if eq {$local_part}{rt} {correspond}{action}}
538
539A0025: You need some internal quoting in there. Exim expands each individual
540 argument separately. Because you have (necessarily) got spaces in your
541 \"${if"\ item, you have to quote that argument. Try
542
543==> command = perl -T /usr/local/rt/bin/rtmux.pl \
544 rt-mailgate helpdesk \
545 "${if eq {$local_part}{rt} {correspond}{action}}"
546
547 \**Warning:**\ If command starts with an item that requires quoting,
548 you cannot just put it in quotes, because a leading quote means that the
549 entire option setting is being quoted. What you have to do is to quote
550 the entire value, and use internally escaped quotes for the ones you
551 really want. For example:
552
553==> command = "\"${if ....}\" arg1 arg2"
554
555 Any backslashes in the expansion items will have to be doubled to stop
556 them being interpreted by the string reader.
557
558
559Q0026: I'm trying to get Exim to connect an alias to a pipe, but it always
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560 gives error code 127, with the comment \*(could mean unable to exec
561 or command does not exist)*\.
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562
563A0026: If your alias entry looks like this:
564
565==> alias: |"/some/command some parameters"
566
567 change it to look like this:
568
569==> alias: "|/some/command some parameters"
570
571
572Q0027: What does the error \*Spool file is locked*\ mean?
573
574A0027: This is not an error. All it means is that when an Exim delivery
575 process (probably started by a queue runner process) looked at a message
576 in order to start delivering it, it found that another Exim process was
577 already busy delivering it. On a busy system this is quite a common
578 occurrence. If you set \"-skip_delivery"\ in the \log_selector\ option,
579 these messages are omitted from the log.
580
581 The only time when this message might indicate a problem is if it is
582 repeated for the same message for a very long time. That would suggest
583 that the process that is delivering the message has somehow got stuck.
584
585
586Q0028: Exim is reporting IP addresses as 0.0.0.0 or 255.255.255.255 instead of
587 their correct values. What's going on?
588
589A0028: You are using a version of Exim built with gcc on an IRIX box.
590 See Q9502.
591
592
593Q0029: I can't seem to figure out why PAM support doesn't work correctly.
594
595A0029: There is a problem using PAM with shadow passwords when the calling
596 program is not running as \/root/\. Exim is normally running as the
8e26e4bf 597 Exim user when authenticating a remote host.
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8e26e4bf 599 (1) One solution can be found at \?http://www.e-admin.de/pam_exim/?\.
495ae4b0 600
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601 (2) PAM 0.72 allows authorization as non-\/root/\, using setuid helper
602 programs. Furthermore, in \(/etc/pam.d/exim)\ you can explicitly
603 specify that this authorization (using setuid helpers) is only
604 permitted for certain users and groups.
495ae4b0 605
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606 (3) Another approach is to authenticate using the \^saslauthd^\ daemon,
607 which has its own interface to PAM. The daemon runs as root, so
608 there is no access problem.
609
610 (4) One suggested solution was to set
611
612==> exim_group=shadow
613
614 in the configuration file, or the equivalent at build time. This is
615 very strongly discouraged. Do not do it! It works, but it's a
616 potential security exposure. Exim is intended to run as a
617 non-privileged user for much of the time. This setting gives it have
618 privileged access to crucial security information all of the time,
619 simply for the purposes of authentication (which Exim will only
620 spend a tiny part of its total time doing). The result is that a
621 successful compromise of the Exim system can give someone direct
622 access to the system passwords.
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623
624
625Q0030: I'm trying to use a query-style lookup for hosts that are allowed to
626 relay, but it is giving really weird errors.
627
628A0030: Does your query contain a colon character? Remember that host lists are
629 colon-separated, so you need to double any colons in the query. This
630 applies even if the query is defined as a macro.
631
632
633Q0031: Exim is rejecting connections from hosts that have more than one IP
634 address, for no apparent reason.
635
636A0031: You are using Solaris 7 or earlier, and have \"nis dns files"\ in
637 \(/etc/nsswitch.conf)\. Change this to \"dns nis files"\ to avoid hitting Sun
638 bug 1154236 (a bad interaction between NIS and the DNS).
639
640
641Q0032: Exim is failing to find the MySQL library, even though is it present
642 within \\LD_LIBRARY_PATH\\. I'm getting this error:
643
644==> /usr/local/bin/exim: fatal: libmysqlclient.so.6: open failed:
645 No such file or directory
646
647A0032: Exim is suid, and \\LD_LIBRARY_PATH\\ is ignored for suid binaries on a
648 Solaris (and other?) systems. What you should be doing is adding
649 \"-R/local/lib/mysql"\ to the same place in the compilation that you added
650 \"-L/local/lib/mysql"\. This tells the binary where to look without
651 needing a path variable.
652
653
654Q0033: What does the error \*lookup of host "xx.xx.xx" failed in yyy router*\
655 mean?
656
657A0033: You configured a \%manualroute%\ router to send the message to xx.xx.xx. When
658 it tried to look up the IP address for that host, the lookup failed
659 with a permanent error. As this is a manual routing, this is a
660 considered to be a serious error which the postmaster needs to know
661 about (maybe you have a typo in your file), and there is little point
662 in keeping on trying. So it freezes the message.
663
664 (1) Don't set up routes to non-existent hosts.
665
666 (2) If you must set up routes to non-existent hosts, and don't want
667 freezing, set the \host_find_failed\ option on the router to do something
668 other than freeze.
669
670
671Q0034: Exim works fine on one host, but when I copied the binary to another
672 identical host, it stopped working (it could not resolve DNS names).
673
674A0034: Is the new host running exactly the same operating system? Most
675 importantly, are the versions of the dynamically loaded libraries
676 (files with names like \(libsocket.so.1)\) the same on both systems? If not,
677 that is probably the cause of the problem. Either arrange for the
678 libraries to be the same, or rebuild Exim from source on the new host.
679
680
681Q0035: I set a \"hosts"\ condition in an ACL to do a lookup in a file of IP
682 addresses, but it doesn't work.
683
684A0035: Did you remember to put \"net-"\ at the start of the the search type? If
685 you set something like this:
686
687==> accept hosts = lsearch;/some/file
688
689 Exim searches the file for the host name, not the IP address. You need
690 to set
691
692==> accept hosts = net-lsearch;/some/file
693
694 to make it use the IP address as the key to the lookup.
695
696
697Q0036: Why do I get the error \*Permission denied: creating lock file hitching
698 post*\ when Exim tries to do a local delivery?
699
700A0036: Your configuration specifies that local mailboxes are all held in
701 single directory, via configuration lines like these (taken from the
702 default configuration):
703
704==> local_delivery:
705 driver = appendfile
706 file = /var/mail/$local_part
707
708 and the permissions on the directory probably look like this:
709
710==> drwxrwxr-x 3 root mail 512 Jul 9 13:48 /var/mail/
711
712 Using the default configuration, Exim runs as the local user when doing
713 a local delivery, and it uses a lock file to prevent any other process
714 from updating the mailbox while it is writing to it. With those
715 permissions the delivery process, running as the user, is unable to
716 create a lock file in the \(/var/mail(\ directory. There are two solutions
717 to this problem:
718
719 (1) Set the \"write"\ and \"sticky bit"\ permissions on the directory, so
720 that it looks like this:
721
722==> drwxrwxrwt 3 root mail 512 Jul 9 13:48 /var/mail/
723
724 The \"w"\ allows any user to create new files in the directory, but
725 the \"t"\ bit means that only the creator of a file is able to remove
726 it. This is the same setting as is normally used with the \(/tmp)\
727 directory.
728
729 (2) Arrange to run the local_delivery transport under a specific group
730 by changing the configuration to read
731
732==> local_delivery:
733 driver = appendfile
734 file = /var/mail/${local_part}
735 group = mail
736
737 The delivery process still runs under the user's uid, but with the
738 group set to \"mail"\. The group permission on the directory allows
739 the process to create and remove the lock file.
740
741 The choice between (1) and (2) is up to the administrator. If the
742 second solution is used, users can empty their mailboxes by updating
743 them, but cannot delete them.
744
f0884f39 745 If your problem involves mail to \/root/\, see also Q0039.
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746
747
748Q0037: I am experiencing mailbox locking problems with Sun's \"mailtool"\ used
749 over a network.
750
751A0037: See Q9705 in the Sun-specific section below.
752
753
754Q0038: What does the error message \*error in forward file (filtering not
755 enabled): missing or malformed local part*\ mean?
756
757A0038: If you are trying to use an Exim filter, you have forgotten to enable
758 the facility, which is disabled by default. In the \%redirect%\ router
759 (in the Exim run time configuration file) you need to set
760
761==> allow_filter = true
762
763 to allow a \(.forward)\ file to be used as an Exim filter. If you are not
764 trying to use an Exim filter, then you have put a malformed address in
765 the \(.forward)\ file.
766
767
768Q0039: I have installed Exim, but now I can't mail to \/root/\ any more. Why is
769 this?
770
771A0039: Most people set up \/root/\ as an alias for the manager of the host. If
772 you haven't done this, Exim will attempt to deliver to \/root/\ as if it
773 were a normal user. This isn't really a good idea because the delivery
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774 process would run as \/root/\. Exim has two trigger guards that stop
775 deliveries running as root. In the build-time configuration, there is a
776 setting called FIXED_NEVER_USERS, which defaults to \"root"\. This
777 setting cannot be overridden. In addition, the default runtime
778 configuration contains the option
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779
780==> never_users = root
781
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782 just to be on the safe side. If you really want to run local deliveries
783 as \/root/\, you must use a version of Exim that was built without the
784 FIXED_NEVER_USERS option, and remove the above line from the runtime
785 configuration, but it would be better to create an alias for \/root/\
786 instead.
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787
788
789Q0040: How can I stop undeliverable bounce messages (e.g. to routeable, but
790 undeliverable, spammer senders) from clogging up the queue for days?
791
792A0040: If at all possible, you should try to avoid getting into this situation
793 in the first place, for example, by verifying recipients so that you
794 do not accept undeliverable messages that lead to these bounces.
795 You can, however, configure Exim to discard failing bounce messages
796 early. Just set \ignore_bounce_errors_after\ to specify a (short) time
797 to keep them for.
798
799
800Q0041: What does the message \*unable to set gid=ddd or uid=ddd (euid=ddd):
801 local delivery to ... transport=ttt*\ mean?
802
803A0041: Have you remembered to make Exim setuid \/root/\? It needs root privilege if
804 it is to do any local deliveries, because it does them ``as the user''.
805 Note also that the partition from which Exim is running (where the
806 binary is installed) must not have the \nosuid\ mount option set. You
807 can check this by looking at its \(/etc/fstab)\ entry (or \(/etc/vfstab)\,
808 depending on your OS).
809
810
811Q0042: My ISP's mail server is rejecting bounce messages from Exim, complaining
812 that they have no sender. The SMTP trace does indeed show that the
813 sender address is \"<>"\. Why is the Sender on the bounce message empty?
814
815A0042: Because the RFCs say it must be. Your ISP is at fault. Send them this
816 extract from RFC 2821 section 6.1 (\*Reliable Delivery and Replies by
817 Email*\):
818
819 If there is a delivery failure after acceptance of a message, the
820 receiver-SMTP MUST formulate and mail a notification message. This
821 notification MUST be sent using a null (\"<>"\) reverse path in the
822 envelope. The recipient of this notification MUST be the address
823 from the envelope return path (or the ::Return-Path:: header line).
824 However, if this address is null (\"<>"\), the receiver-SMTP MUST NOT
825 send a notification.
826
827 The reason that bounce messages have no sender is so that they
828 themselves cannot provoke further bounces, as this could lead to a
829 unending exchange of undeliverable messages.
830
831
832Q0043: What does the error \*Unable to get interface configuration: 22 Invalid
833 argument*\ mean?
834
835A0043: This is an error that occurs when Exim is trying to find out the all the
836 IP addresses on all of the local host's interfaces. If you have lots of
837 virtual interfaces, this can occur if there are more than around 250 of
838 them. The solution is to set the option \local_interfaces\ to list just
839 those IP addresses that you want to use for making and receiving SMTP
840 connections.
841
842
843Q0044: What does the error \*Failed to create spool file*\ mean?
844
845A0044: Exim has been unable to create a file in its spool area in which to
846 store an incoming message. This is most likely to be either a
847 permissions problem in the file hierarchy, or a problem with the uid
848 under which Exim is running, though it could be something more drastic
849 such as your disk being full.
850
851 If you are running Exim with an alternate configuration file using a
852 command such as \"exim -C altconfig..."\, remember that the use of -C
cc5fdbc2 853 takes away Exim's root privilege, unless \\TRUSTED_CONFIG_LIST\\
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854 is set in \(Local/Makefile)\ and the corresponding file contains a
855 prefix which matches the alternative configuration file being used.
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856
857 Check that you have defined the spool directory correctly by running
858
859==> exim -bP spool_directory
860
861 and examining the output. Check the mode of this directory. It should
862 look like this, assuming you are running Exim as user \/exim/\:
863
864==> drwxr-x--- 6 exim exim 512 Jul 16 12:29 /var/spool/exim
865
866 If there are any subdirectories already in existence, they should have
867 the same permissions, owner, and group. Check also that you haven't got
868 incorrect permissions on superior directories (for example, \(/var/spool)\).
869 Check that you have set up the Exim binary to be setuid \/root/\. It should
870 look like this:
871
872==> -rwsr-xr-x 1 root xxx 502780 Jul 16 14:16 exim
873
874 Note that it is not just the owner that must be \/root/\, but also the third
875 permission must be \"s"\ rather than \"x"\.
876
877
878Q0045: I see entries in the log that mention two different IP addresses for the
879 same connection. Why is this? For example:
880
881==> H=tip-mp8-ncs-13.stanford.edu ([36.173.0.189]) [36.173.0.156]
882
883A0045: The actual IP address from which the call came is the final one.
884 Whenever there's something in parentheses in a host name, it is what the
885 host quoted as the domain part of an SMTP HELO or EHLO command. So in
886 this case, the client, despite being 36.173.0.156, issued the command
887
888==> EHLO [36.173.0.189]
889
890 when it sent your server the message. This is, of course, very
891 misleading.
892
893
894Q0046: A short time after I start Exim I see a defunct zombie process. What
895 is causing this?
896
897A0046: Your system must be lightly loaded as far as mail is concerned. The
898 daemon sets off a queue runner process when it is started, but it only
899 tidies up completed child processes when it wakes up for some other
900 reason. When there's nothing much going on, you occasionally see
901 defunct processes like this waiting to be dealt with. This is
902 perfectly normal.
903
904
905Q0047: On a reboot, or a restart of the mail system, I see the message \*Mailer
906 daemons: exim abandoned: unknown, malformed, or incomplete option
907 -bz sendmail*\. What does this mean?
908
909A0047: \-bz-\ is a Sendmail option requesting it to create a `configuration freeze
910 file'. Exim has no such concept and so does not support the option. You
911 probably have a line like
912
913==> /usr/lib/sendmail -bz
914
4c04137d 915 in some start-up script (e.g. \(/etc/init.d/mail)\) immediately before
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916
917==> /usr/lib/sendmail -bd -q15m
918
919 The first of these lines should be commented out.
920
921
922Q0048: Whenever exim restarts it takes up to 3-5 minutes to start responding on
923 the SMTP port. Why is this?
924
925A0048: Something else is hanging onto port 25 and not releasing it. One place
926 to look is \(/etc/inetd.conf)\ in case for any reason an SMTP stream is
927 configured there.
928
929
930Q0049: What does the log message \*no immediate delivery: more than 10 messages
931 received in one connection*\ mean?
932
933A0049: A remote MTA sent a number of messages in a single SMTP session. Exim
934 limits the number of immediate delivery processes it creates as a
935 result of a single SMTP connection, in order to avoid creating a zillion
936 processes on systems that can have many incoming connections. If you are
937 dialing in to collect mail from your ISP, you should probably set
938 \smtp_accept_queue_per_connection\ to some number larger than 10, or
939 arrange to start a queue runner for local delivery (using \-ql-\)
940 immediately after collecting the mail.
941
942
943Q0050: I am getting complaints from a customer who uses my Exim server for
944 relaying that they are being blocked with a \*Too many connections*\
945 error.
946
947A0050: See \smtp_accept_max\, \smep_accept_max_per_host\ and \smtp_accept_reserve\.
948
949
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950Q0051: When I test my system filter with \-bf-\, I get the error \*filtering
951 command "fail" is disabled*\. Why is this?
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952
953A0051: Use the \-bF-\ option to test system filters. This gives you access to the
954 freeze and fail actions.
955
956
957Q0052: What does \*ridiculously long message header*\ in an error report mean?
958
959A0052: There has to be some limit to the length of a message's header lines,
960 because otherwise a malefactor could open an SMTP channel to your host,
961 start a message, and then just send characters continuously until your
8e26e4bf 962 host runs out of memory. (Exim stores all the header lines in main
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963 memory while processing a message). For this reason a limit is imposed
964 on the total amount of memory that can be used for header lines. The
965 default is 1MB, but this can be changed by setting \\HEADER_MAXSIZE\\ in
966 \(Local/Makefile)\ before building Exim. Exceeding the limit provokes
967 the ``ridiculous'' error message.
968
969
970Q0053: Exim on my host responds to a connection with \"220 *****..."\ and
971 won't understand \\EHLO\\ commands.
972
973A0053: This is the sign of a Cisco Pix ``Mailguard'' sitting in front of your
974 MTA. Pix breaks ESMTP and only does SMTP. It is a nuisance when you have
975 a secure MTA running on your box. Something like ``no fixup protocol
976 smtp 25'' in the Pix configuration is needed. It may be possible to do
977 this by logging into the Pix (using \^telnet^\ or \^ssh^\) and typing
978 \"no fixup smtp"\ to its console. (You may need to use other commands
979 before or after to set up configuration mode and to activate a changed
980 configuration. Consult your Pix documentation or expert.) See also
981 Q0078.
982
983
984Q0054: I'm getting an Exim configuration error \*unknown rewrite flag
985 character (m) in line 386*\ but I haven't used any flags on my rewriting
986 rules.
987
988A0054: You have probably forgotten to quote a replacement string that contains
989 white space.
990
991
992Q0055: What does the error \*Failed to open wait-remote_smtp database: Invalid
993 argument*\ mean?
994
995A0055: This is something that happens if you have existing DBM hints files when
996 you install a new version of Exim that is compiled to use a different or
997 upgraded DBM library. The simplest thing to try is
998
999==> rm /var/spool/exim/db/*
1000
1001 This removes all the hints files. Exim will start afresh and build new
1002 ones. If the symptom recurs, it suggests there is some problem with your
1003 DBM library.
1004
1005
1006Q0056: We are using Exim to send mail from our web server. However, whenever a
1007 user sends an email it gets sent with the return path (envelope sender)
1008 //apache@server_name.com// because the PHP script is running as
1009 \/apache/\.
1010
1011A0056: You need to include \/apache/\ in the \trusted_users\ configuration option.
1012 Only trusted users are permitted to specify senders when mail is passed
1013 to Exim via the command line.
1014
1015
1016Q0057: We've got people complaining about attachments that don't show up
1017 as attachments, but are included in the body of the message.
1018
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1019A0057: In the past, these symptoms could be seen when some software passed a
1020 CRLF line terminated message via the command line, because Exim expected
1021 lines to be terminated by LF only, and so it preserved the CRs as data.
1022 Modern versions of Exim (4.21 or later) use heuristics to try to do the
1023 right thing with line endings.
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1024
1025
1026Q0058: What does the error \*failed to open DB file \(/var/spool/exim/db/retry)\:
1027 File exists*\ mean?
1028
1029A0058: This error is most often caused when a hints file that was written with
1030 one version of the Berkeley DB library is read by another version.
1031 Sometimes this can happen if you change from a binary version of Exim to
1032 a locally compiled version. Or it can happen if you compile and install
1033 a new version of Exim after changing Berkeley DB versions. You can find
1034 out which version your Exim is using by running:
1035
1036==> ldd /usr/sbin/exim
1037
1038 The solution to the problem is to delete all the files in the
1039 \(/var/spool/exim/db)\ directory, and let Exim recreate them.
1040
1041
1042Q0059: When my Outlook Express 6.0 client sends a STARTTLS command to begin a
1043 TLS session, Exim doesn't seem to receive it. The Outlook log shows
1044 this:
1045
1046==> SMTP: 14:19:27 [tx] STARTTLS
1047 SMTP: 14:19:27 [rx] 500 Unsupported command.
1048
1049 but the Exim debugging output shows this:
1050
1051==> SMTP<< EHLO xxxx
1052 SMTP>> 250-yyyy Hello xxxx [nnn.nnn.nnn.nnn]
1053 250-SIZE 52428800
1054 250-PIPELINING
1055 250-AUTH CRAM-MD5 PLAIN LOGIN
1056 250-STARTTLS
1057 250 HELP
1058 SMTP<< QUIT
1059
1060A0059: Turn off scanning of outgoing email in Norton Antivirus. If you aren't
1061 running Norton Antivirus, see if you are running some other kind of SMTP
1062 proxying, either on the client or on a firewall between the client and
1063 server. ``Unsupported command'' is not an Exim message.
1064
1065
1066Q0060: Why am I getting the error \*failed to expand \"/data/lists/lists/${lc"\
1067 for require_files: \"${lc"\ is not a known operator*\ for this setting:
1068
1069==> require_files = MAILMAN_HOME/lists/${lc:$local_part}/config.db
1070
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1071A0060: The value of \"require_files"\ is a list in which each item is
1072 separately expanded. In other words, the splitting into items happens
1073 before the string expansion. You need either to double the colon, or
1074 switch to a different list separator.
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1075
1076
1077Q0061: What does the error \*Too many ``Received'' headers - suspected mail
1078 loop*\ mean?
1079
1080A0061: Whenever a message passes through an MTA, a ::Received:: header gets
1081 added. Exim counts the number of these headers in incoming messages. If
1082 there are more than the value of \received_headers_max\ (default 30),
1083 Exim assumes there is some kind of mail routing loop occurring. For
1084 example, host A passes the message to host B, which immediately passes
1085 it back to host A. Check the ::Received:: headers and the mail logs to
1086 determine exactly what is going on.
1087
1088 One common cause of this problem is users with accounts on both systems
1089 who set up each one to forward to the other, thinking that will cause
1090 copies of all messages to be delivered on both of them.
1091
1092
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1093Q0062: When I try to start an Exim daemon with \-bd-\ it crashes. I ran a
1094 debugger and discovered that the crash is happening in the function
1095 \^^getservbyname()^^\. What's going on?
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1096
1097A0062: What have you got in the file \(/etc/nsswitch.conf)\? If it contains this
1098 line:
1099
1100==> services: db files
1101
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1102 try removing the \"db"\. Your system is trying to look in some kind of
1103 database before searching the file \(/etc/services)\, and there is an
1104 incompatibility the is causing the function \^^getservbyname()^^\ crash.
1105 This is an OS problem. See, for instance:
1106
1107 \?http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=129025?\
1108
1109 Another workaround in Exim is to set
1110
1111==> daemon_smtp_port = 25
1112
1113 in the configuration, to stop Exim calling \^^getservbyname()^^\.
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1114
1115
1116Q0063: When I try to start an Exim daemon, nothing happens. There is no
1117 process, and nothing is written to the Exim log.
1118
1119A0063: Check to see if anything is written to \(syslog)\. This problem can be
1120 caused by a permission problem that stops Exim from writing to its log
1121 files, especially if you've specified that they should be written
1122 somewhere other than under Exim's spool directory. You could also try
1123 running the daemon with debugging turned on.
1124
1125
1126Q0064: When I run \"exim -d test@domain"\ it delivers fine, but when I send a
1127 message from the \^mail^\ command, I get \*User unknown*\ and the mail
1128 is saved in \(dead.letter)\.
1129
1130A0064: It looks as if Exim isn't being called by \^mail^\; instead it is
1131 calling some other program (probably Sendmail). Try running the command
1132
1133==> /usr/sbin/sendmail -bV
1134
1135 (If you get \*No such file or directory*\ or \*Command not found*\ you
1136 are running Solaris or IRIX. Try again with \(/usr/lib/sendmail)\.) The
1137 output should be something like this:
1138
1139==> Exim version 4.05 #1 built 13-Jun-2002 10:27:15
1140 Copyright (c) University of Cambridge 2002
1141
1142 If you don't see this, your Exim installation isn't fully operational.
1143 If you are running FreeBSD, see Q9201. For other systems, see Q0114.
1144
1145
1146Q0065: When (as \/root/\) I use -C to run Exim with an alternate configuration
1147 file, it gives an error about being unable to create a spool file when
1148 trying to run an \%autoreply%\ transport. Why is this?
1149
1150A0065: When Exim is called with -C, it passes on -C to any instances of itself
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1151 that it calls (so that the whole sequence uses the same config file).
1152 However, Exim gives up its root privilege if any user except \/root\/
1153 passes a -C option to use a non-default configuration file, and that
1154 includes the case where Exim re-execs itself to regain root privilege.
1155 Thus it can't write to the spool.
1156
cc5fdbc2 1157 The fix for this is to use the \\TRUSTED_CONFIG_LIST\\ build-time
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1158 option. This defines a file containing a list of 'trusted' prefixes for
1159 configuration files. Any configuration file specified with -C, if it
1160 matches a prefix listed in that file, will be used without dropping root
1161 privileges (as long as it is not writeable by a non-root user).
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1162
1163
1164Q0066: What does the message \*unable to set gid=xxx or uid=xxx*\ mean?
1165
1166A0066: This message is given when an Exim process is unable to change uid or
1167 gid when it needs to, because it does not have root privilege. This is a
1168 serious problem that prevents Exim from carrying on with what it is
1169 doing. The two most common situations where Exim needs to change uid/gid
1170 are doing local deliveries and processing users' filter files. There are
1171 two common causes of this error:
1172
1173 (1) You have forgotten to make the exim binary setuid to \/root/\. This
1174 means that it can never change uid/gid in any situation. Also, the
1175 setuid binary must reside on a disk partition that does not have the
1176 \"nosuid"\ mount option set.
1177
1178 (2) The exim binary is setuid, but you have configured Exim so that,
1179 while trying to verify an address at SMTP time, it runs a router
1180 that needs to change uid/gid. Because Exim runs as \/exim/\ and not
1181 \/root/\ while receiving messages, the router is unable to change
1182 uid and therefore it cannot operate. The usual example of this is a
1183 \%redirect%\ router for users' filter files.
1184
1185 Setting the \user\ or \check_local_user\ options on a \redirect\
1186 router causes this to happen (except in the special case when the
1187 redirection list is provided by the \data\ option and does not
1188 contain \":include:"\).
1189
1190 The solution is to set \no_verify\ on the router that is causing the
1191 problem. This means that it is skipped when an address is being
1192 verified. In ``normal'' configurations where the router is indeed
1193 handling users' filter files, this is quite acceptable, because you
1194 do not usually need to process a filter file in order to verify that
1195 the local part is valid. See, for example, the \%userforward%\
1196 router in the default configuration.
1197
1198
1199Q0067: What does the error \*too many unrecognized commands*\ mean?
1200
1201A0067: There have been instances of network abuse involving mail sent out by
1202 web servers. In most cases, unrecognizable commands are sent as part of
1203 the SMTP session. A real MTA never sends out such invalid commands. Exim
1204 allows a few unrecognized commands in a session to permit humans who are
1205 testing to make a few typos (it responds with a 5xx error). However, if
1206 Exim receives too many such commands, it assumes that it is dealing with
1207 an abuse of some kind, and so it drops the connection.
1208
1209
1210Q0068: Exim times out when trying to connect to some hosts, though those hosts
1211 are known to be up and running. What's the problem?
1212
1213A0068: There could be a number of reasons for this (see also Q0017). The
1214 obvious one is that there is a networking problem between the hosts.
1215 If you can ping between the hosts or connect in other ways, the problem
1216 might be caused by ECN (Explicit Congestion Notification) being enabled
1217 in your kernel. ECN uses TCP flags originally assigned to TOS - it's a
1218 "new" invention, and some hosts and routers are known to be confused if
1219 a client uses it. If you are running Linux, you can turn ECN off by
1220 running this command:
1221
1222==> /bin/echo "0" > /proc/sys/net/ipv4/tcp_ecn
1223
1224 This has also been reported to cure web connection problems from Mozilla
1225 and Netscape browsers in Linux when there were no problems with Windows
1226 Netscape browsers.
1227
1228
1229Q0069: What does the error \*SMTP data timeout (message abandoned) on connection
1230 from...*\ mean?
1231
1232A0069: It means that there was a timeout while Exim was reading the contents of
1233 a message on an incoming SMTP connection. That is, it had successfully
1234 accepted a MAIL command, one or more RCPT commands, and a DATA command,
1235 and was in the process of reading the data itself. The length of timeout
1236 is controlled by the \smtp_receive_timeout\ option.
1237
1238 If you get this error regularly, the cause may be incorrect handling of
1239 large packets by a router or firewall. The maximum size of a packet is
1240 restricted on some links; routers should split packets that are larger.
1241 There is a feature called ``path MTU discovery'' that enables a sender
1242 to discover the maximum packet size over an entire path (multiple
1243 Internet links). This can be broken by misconfigured firewalls and
1244 routers. There is a good explanation at \?http://www.netheaven.com/pmtu.html?\.
1245 Reducing the MTU on your local network can sometimes work round this
1246 problem. See Q0017 (3) for further discussion.
1247
1248
1249Q0070: What does the error \*SMTP command timeout on connection from...*\ mean?
1250
1251A0070: Exim was expecting to read an SMTP command from the client, but no
1252 command was read within the \smtp_receive_timeout\ time limit.
1253
1254
1255Q0071: What does the error \*failed to open DB file \(/var/spool/exim//db/retry)\:
1256 Illegal argument*\ mean?
1257
1258A0071: See Q0058. The cause of this error is usually the same.
1259
1260
1261Q0072: Exim will deliver to normal aliases, and aliases that are pipes or
1262 files, but it objects to aliases that involve \":include:"\ items,
1263 complaining that it can't change gid or uid. Why is this?
1264
1265A0072: See Q0066 for a general answer. The problem happens during verification
1266 of an incoming SMTP message, not during delivery itself. In this
1267 particular case, you must have set up your aliasing router with a \user\
1268 setting. This causes Exim to change uid/gid when reading \":include:"\
1269 files. If you do not need the detailed verification provided by the
1270 router, the easy solution is to set \no_verify\ so that the router isn't
1271 used during verification.
1272
1273 Otherwise, if you set \user\ on the router in order to provide a user
1274 for delivery to pipes or files, one solution is to put the \user\
1275 setting on the transports instead of on the router. You may need to
1276 create some special transports just for this router. The alternative is
1277 to supply two different routers, one with \user\ and \no_verify\, and
1278 the with \verify_only\ but no \user\ setting.
1279
1280
1281Q0073: I'm seeing log file corruption, with parts of log lines getting mangled
1282 by other log entries.
1283
1284A0073: The only time this has been seen is when several servers were writing to
1285 the same log files over NFS. Exim assumes that its log file is on local
1286 disk, and using NFS, especially for more than one server, will not work.
1287
1288
1289Q0074: What does the error message \*remote delivery process count got out of
1290 step*\ mean?
1291
1292A0074: Exim uses subprocesses for remote deliveries; this error means that the
1293 master process expected to have a child process running, but found there
1294 were none. Prior to release 4.11, this error could be caused by running
1295 Exim under \^strace^\ on a Linux system, because stracing causes
1296 children to be ``stolen'' such that a parent that tries to wait for
1297 ``any of my children'' is told that it has none. Current releases of
1298 Exim have code to get round this problem.
1299
1300
1301Q0075: I'm using LDAP, and some email addresses that contain special characters
1302 are causing parsing errors in my LDAP lookups.
1303
1304A0075: You should be using \"${quote_ldap:$local_part}"\ instead of just
1305 \"$local_part"\ in your lookups.
1306
1307
1308Q0076: I've configured Exim to use \^syslog^\ for its logs, with the main and
1309 reject logs sent to different files, but whenever a message is rejected,
1310 I get one message on the reject log and two messages on the main log.
1311
1312A0076: You are probably putting your reject items into the main log as well;
1313 remember \^syslog^\ levels are inclusive (for example, \"mail.info"\
1314 includes all higher levels, so a \"mail.notice"\ message will be caught
1315 by a \"mail.info"\ descriptor).
1316 Test this by running the command:
1317
f0884f39 1318==> logger -p mail.notice test
495ae4b0 1319
8e26e4bf
PH
1320 and seeing which logs it goes into. From Exim release 4.31 it is
1321 possible to disable the rejectlog by setting \write_rejectlog\ false.
495ae4b0
PH
1322
1323
1324Q0077: I've installed Exim and it is delivering mail just fine. However, when I
1325 try to read mail from my PC I get \*connection rejected*\ or \*unable to
1326 connect*\.
1327
1328A0077: See Q5021.
1329
1330
1331Q0078: Exim is logging the unknown SMTP command \"XXXX"\ from my client hosts,
1332 and they are unable to authenticate.
1333
1334A0078: This is a sign of a Cisco PIX firewall getting in the way. It does not
1335 support ESMTP, and turns EHLO commands into XXXX. You should configure
1336 the Pix to leave SMTP alone; see Q0053 for how to do this.
1337
1338
1339Q0079: Our new PIX firewall is causing problems with incoming mail. How can
1340 this be fixed?
1341
1342A0079: See Q0053 and Q0078. If some messages get through and others do not,
1343 see also Q0017.
1344
1345
1346Q0080: Am I to understand that the database lookups must only return one value?
1347 They can not return a list of values? The documentation seems to
1348 indicate that it's possible to return a list.
1349
1350A0080: Lookups can be used in two different situations, and what they return is
1351 different in the two cases. (Be thankful Exim 3 is gone; there was yet
1352 another case!)
1353
1354 (1) You can use a lookup in any expanded string. The syntax is
1355
1356==> ${lookup ..... }
1357
1358 In this case, whatever is looked up replaces the expansion item. It
1359 may be one value or a list of values. Whether a single value or a
1360 list is acceptable or not depends on where you are using the string
1361 expansion. If it is for an option that expects just one value, then
1362 only one value is allowed (for example).
1363
1364 (2) You can make use of the lookup mechanism to test whether something
1365 (typically a host name or IP address) is in a list. For example,
1366
1367==> hosts = a : b : c
1368
1369 in an ACL tests whether the calling host's name matches ``a'', or
1370 ``b'', or ``c''. Now, suppose you want to keep the list of names in
1371 a database, or cdb file, or NIS map, or... By writing
1372
1373==> hosts = pgsql;select ....
1374
1375 you are saying to Exim: ``Run this lookup; if it succeeds, behave as
1376 if the host is in the list; if it fails, the host is not in the
1377 list.'' You are using the indexing mechanism of the database as a
1378 fast way of checking a list. A simpler example is
1379
1380==> hosts = lsearch;/some/file
1381
1382 where the file contains the list of hosts to be searched.
1383
1384 The complication happens when a list is first expanded before being
1385 interpreted as a list. This happens in a lot of cases. You can therefore
1386 write either of these:
1387
1388==> hosts = cdb;/some/file
1389 hosts = ${lookup{something}cdb{/some/file}}
1390
1391 but they have different meanings. The first means ``see if the host name
1392 is in the list in this file''. The second means ``run this lookup and
1393 use the result of the lookup as a list of host items to check''. In the
1394 second case, the list could contain multiple values (colon separated),
1395 and one of those values could even be ``cdb;/some/file''.
1396
1397 Flexibility does lead to complexity, I'm afraid.
1398
1399
1400Q0081: What does \*error in redirect data: included file xxxx is too big*\
1401 mean?
1402
1403A0081: You are trying to include a very large file in a redirection list, using
1404 the \":include:"\ feature. Exim has a built-in limit on the size, as a
1405 safety precaution. The default is 1 megabyte. If you want to increase
1406 this, you have to rebuild Exim. In your \(Local/Makefile)\, put
1407
1408==> MAX_INCLUDE_SIZE = whatever
1409
1410 and then rebuild Exim. The value is a number of bytes, but you can give
1411 it as a parenthesized arithmetic expression such as \"(3*1024*1024)"\.
1412 However, an included file of more than a megabyte is likely to be quite
1413 inefficient. How many addresses does yours contain? You get the best
1414 performance out of Exim if you arrange to send mailing list messages
1415 with no more than about 100 recipients (in order to get parallelism in
1416 the routing).
1417
1418
1419Q0082: What does \*relocation error: /lib/libnss_dns.so.2: symbol
1420 __libc_res_nquery, version GLIBC_PRIVATE not defined in file
1421 libresolv.so.2 with link time reference*\ mean?
1422
1423A0082: You have updated \^glibc^\ while an Exim daemon is running. Stop and
1424 restart the daemon.
1425
1426
1427Q0083: Netscape on Unix is sending messages containing an unqualified user name
1428 in the ::Sender:: header line, which Exim is rejecting because I have
1429 set \"verify = header_syntax"\. How can I fix this?
1430
1431A0083: The only thing you can do in Exim is to set the
1432 \sender_unqualified_hosts\ option to allow unqualified sender addresses
1433 form the relevant hosts; of course, this applies to all sender
1434 addresses, not just the ::Sender:: header line.
1435
1436 Alternatively, you can configure Netscape not to include the header line
1437 in the first place. Add the following line to the
1438 \($HOME/.netscape/preferences.js)\ and \($HOME/.netscape/liprefs.js)\
1439 files:
1440
1441==> user_pref("mail.suppress_sender_header", true);
1442
8e26e4bf 1443 Netscape must be shut down while doing this.
495ae4b0
PH
1444
1445
1446Q0084: I want to set up an alias that pipes a message to \^gpg^\ and then pipes
1447 the result to \^mailx^\ to resubmit the message, but when I use my
1448 tested command in an alias file, I get an error from \^gpg^\.
1449
1450A0084: Probably you are using a shell command with two pipe symbols in it. An
1451 alias like this:
1452
1453==> gpg-xxx: "|gpg <options> | mailx <options"
1454
1455 does not work, because Exim does not run pipes under a shell by default.
1456 You must call a shell explicitly if you want to make use of the shell's
1457 features for double-piping, either by piping to \"/bin/sh"\ with a
1458 suitable \"-c"\ option, or by piping to a shell script.
1459
1460
1461Q0085: I see a lot of \*rejected EHLO ... syntactically invalid argument(s)*\.
1462 I know it's because of the underscore in the host name, but is there a
1463 switch to allow Exim to accept mail from such hosts?
1464
1465A0085: Yes. Add this to your configuration:
1466
1467==> helo_allow_chars = _
1468
1469 For more seriously malformed host names, see \helo_accept_junk_hosts\.
1470 See also Q0732.
1471
1472
1473Q0086: What does \*SMTP protocol violation: synchronization error (next input
1474 sent too soon)*\ mean?
1475
1476A0086: SMTP is a ``lock-step'' protocol, which means that, at certain points in
1477 the protocol, the client must wait for the server to respond before
1478 sending more data. Exim checks for correct behaviour, and issues this
1479 error if the client sends data too soon. This protects against
1480 malefactious clients who send a bunch of SMTP commands (usually to
1481 transmit spam) without waiting for any replies.
1482
8e26e4bf
PH
1483 This error is also provoked if a client unexpectedly tries to start up a
1484 TLS session immediately on connection, without using the STARTTLS
1485 command. See Q1707 for a discussion of this case.
495ae4b0
PH
1486
1487
1488Q0087: What does \*rejected after DATA: malformed address: xx@yy may not follow
8e26e4bf 1489 <xx@yy> : failing address in "from" header*\ mean?
495ae4b0
PH
1490
1491A0087: Your DATA ACL contains
1492
1493==> verify = header_syntax
1494
1495 and an incoming message contained the line
1496
1497==> From: xx@yy <xx@yy>
1498
1499 This is syntactically invalid. The contents of an address in a header
1500 line are either just the address, or a ``phrase'' followed by an address
1501 in angle brackets. In the latter case, the ``phrase'' must be quoted if
1502 it contains special characters such as @. The following are valid
1503 versions of the bad header:
1504
1505==> From: xx@yy
1506 From: "xx@yy" <xx@yy>
1507
1508 though why on earth anything generates this kind of redundant nonsense I
1509 can't think.
1510
1511
1512Q0088: The Windows mailer SENDFILE.EXE sometimes hangs while trying to send a
1513 message to Exim 4, and eventually times out. It worked flawlessly with
1514 Exim 3. What has changed?
1515
1516A0088: Exim 4 sets an obscure TCP/IP parameter called TCP_NODELAY. This
1517 disables the "Nagle algorithm" for the TCP/IP transmission. The Nagle
1518 algorithm can improve network performance in interactive situations such
1519 as a human typing at a keyboard, by buffering up outgoing data until the
1520 previous packet has been acknowledged, and thereby reducing the number
1521 of packets used. This is not relevant for mail transmission, which
1522 mostly consists of quite large blocks of data; setting TCP_NODELAY
1523 should improve performance. However, it seems that some Windows clients
1524 do not function correctly if the server turns off the Nagle algorithm.
1525 If you are using Exim 4.23 or later, you can set
1526
1527==> tcp_nodelay = false
1528
1529 This stops Exim setting TCP_NODELAY on the sockets created by the
1530 listening daemon.
1531
1532
1533Q0089: What does the error \*kernel: application bug: exim(12099) has SIGCHLD
1534 set to SIG_IGN but calls wait()*\ mean?
1535
8e26e4bf
PH
1536A0089: This was a bad interaction between a change to the Linux kernel and some
1537 ``belt and braces'' programming in Exim. The following explanation is
1538 taken from Exim's change log:
495ae4b0
PH
1539
1540 When Exim is receiving multiple messages on a single connection, and
aded2255 1541 spinning off delivery processes, it sets the SIGCHLD signal handling to
495ae4b0
PH
1542 SIG_IGN, because it doesn't want to wait for these processes. However,
1543 because on some OS this didn't work, it also has a paranoid call to
1544 \^waitpid()^\ in the loop to reap any children that have finished. Some
1545 versions of Linux now complain (to the system log) about this
1546 ``illogical'' call to \^waitpid()^\. I have therefore put it inside a
1547 conditional compilation, and arranged for it to be omitted for Linux.
1548
1549 I am pretty sure I caught all the places in Exim where this happened.
1550 However, there are still occasional reports of this error. I have not
1551 heard of any resolutions, but my current belief is that they are caused
1552 by something that Exim calls falling foul of the same check. There was
1553 at one time a suspicion that the IPv6 stack was involved.
1554
1555
1556Q0090: I can't seem to get a pipe command to run when I include a \"${lookup"\
1557 expansion in it.
1558
1559A0090: See Q0025.
1560
1561
1562Q0091: Why is Exim giving the error \*Failed to send message from address_reply
1563 transport*\ when I run it using -C to specify an alternate
1564 configuration?
1565
1566A0091: See Q0065.
1567
1568
8e26e4bf 1569Q0092: The error message \*Program received signal SIGINT, Interrupt.*\ occurs
2683a02a 1570 when I try to use Exim with PostgreSQL.
8e26e4bf
PH
1571
1572A0092: Check that you have not set
2683a02a
PH
1573
1574==> log_statement=true
1575
8e26e4bf
PH
1576 in the PostgreSQL configuration file. It seems that this causes
1577 PostgreSQL to return logging information as the first row in a query
1578 result, which totally confuses Exim.
2683a02a
PH
1579
1580
495ae4b0
PH
1581
15821. BUILDING AND INSTALLING
1583
1584Q0101: I'm having a problem with an Exim RPM.
1585
1586A0101: Normally the thing to do if you have a problem with an RPM package is
1587 to contact the person who built the package first, not the person who
1588 made the software that's in the package. You can usually find out who
1589 made a package using the following command:
1590
1591==> rpm --query --package --queryformat '%{PACKAGER}\n' <rpm-package-file>
1592
1593 where \[rpm-package-file]\ is the actual file, e.g. \(exim-3.03-2.i386.rpm)\.
1594 Or, if the package is installed on your system:
1595
1596==> rpm --query --queryformat '%{PACKAGER}\n' <package-name>
1597
1598 where \[package-name]\ is the name component of the package, e.g. \"exim"\.
1599 If the packager is unable or unwilling to help, only then should you
1600 contact the actual author or associated mailing list of the software.
1601
1602 If you discover through the querying process that you can't tell who
1603 the person (or company or group) is who built the package, or that they
1604 no longer exist at the given address, then you should reconsider
1605 whether you want a package from an unknown source on your system.
1606
1607 If you discover through the querying process that you yourself are the
1608 person who built the package, then you should either (a) contact the
1609 author or associated mailing list, or (b) reconsider whether you ought
1610 to be building and distributing RPM packages of software you don't
1611 understand.
1612
1613 Similar rules of thumb govern other binary package formats, including
1614 debs, tarballs, and POSIX packages.
1615
1616
1617Q0102: I can't get Exim to compile with Berkeley DB version 2.x or 3.x.
1618
1619A0102: Have you set \"USE_DB=yes\" in \(Local/Makefile)\? This causes Exim to use the
1620 native interface to the DBM library instead of the compatibility
1621 interface, which needs a header called \(ndbm.h)\ that may not exist on your
1622 system.
1623
1624
1625Q0103: I'm getting an \*undefined symbol*\ error for \"hosts_ctl"\ when I try to
1626 build Exim. (On some systems this error is \*undefined reference to
1627 'hosts_ctl'*\.)
1628
1629A0103: You should either remove the definition of \\USE_TCP_WRAPPERS\\ or add
1630 \"-lwrap"\ to your \\EXTRALIBS\\ setting in Local/Makefile.
1631
1632
1633Q0104: I'm about to upgrade to a new Exim release. Do I need to ensure the
1634 spool is empty, or take any other special action?
1635
1636A0104: It depends on where you are coming from.
1637
1638 (1) If you are changing to release 4.00 or later from a release prior to
1639 4.00, you will need to make changes to the run time configuration file.
1640 See the file \(doc/Exim4.upgrade)\ for details. If you are coming from
1641 before release 3.00, you should also see \(doc/Exim3.upgrade)\.
1642
1643 (2) If you are upgrading from an Exim 4 release to a later release, you
1644 do not need to take special action. New releases are made backwards
1645 compatible with old spool files and hints databases, so that upgrading
1646 can be done on a running system. All that should be necessary is to
1647 install a new binary and then HUP the daemon.
1648
8e26e4bf
PH
1649 \**Warning**\: If you have changed the release of your DBM library, so
1650 that your new Exim is linked with a different release than the old one,
1651 you may encounter errors when Exim attempts to access the old hints
1652 databases. See Q0055.
1653
495ae4b0
PH
1654
1655Q0105: What does the error \*install-info: command not found*\ mean?
1656
1657A0105: You have set \\INFO_DIRECTORY\\ in your \(Local/Makefile)\, and Exim is trying
1658 to install the Texinfo documentation, but cannot find the command called
1659 \(install-info)\. If you have a version of Texinfo prior to 3.9, you
1660 should upgrade. Otherwise, check your installation of Texinfo to see why
1661 the \(install-info)\ command is not available.
1662
1663
1664Q0106: Exim doesn't seem to be recognizing my operating system type correctly,
1665 and so is failing to build.
1666
1667A0106: Run the command \"scripts/os-type -generic"\. The output should be one of
1668 the known OS types, and should correspond to your operating system. You
1669 can see which OS are supported by obeying \"ls OS/Makefile-*"\ and looking
1670 at the file name suffixes.
1671
1672 If there is a discrepancy, it means that the script is failing to
1673 interpret the output from the \"uname"\ command correctly, or that the
1674 output is wrong. Meanwhile, you can build Exim by obeying
1675
1676==> EXIM_OSTYPE=xxxx make
1677
1678 instead of just \"make"\, provided you are running a Bourne-compatible
1679 shell, or otherwise by setting \\EXIM_OSTYPE\\ correctly in your
1680 environment. It is probably best to start again from a clean
1681 distribution, to avoid any wreckage left over from the failed attempt.
1682
1683
1684Q0107: Exim fails to build, complaining about the absence of the \"killpg"\
1685 function.
1686
1687A0107: This function should be present in all modern flavours of Unix. If you
1688 are using an older version, you should be able to get round the problem
1689 by inserting
1690
1691==> #define killpg(pgid,sig) kill(-(pgid),sig)
1692
1693 into the file called \(OS/os.h-xxx)\, where xxx identifies your operating
1694 system, and is the output of the command \"scripts/os-type -generic"\.
1695
1696
1697Q0108: I'm getting an unresolved symbol \"ldap_is_ldap_url"\ when trying to build
1698 Exim.
1699
1700A0108: You must have specified \"LOOKUP_LDAP=yes"\ in the configuration. Have you
1701 remembered to set \"-lldap"\ somewhere (e.g. in \\LOOKUP_LIBS\\)? You need that
1702 in order to get the LDAP library scanned when linking.
1703
1704
1705Q0109: I'm getting an unresolved symbol \"mysql_close"\ when trying to build Exim.
1706
1707A0109: You must have specified \"LOOKUP_MYSQL=yes"\ in the configuration. Have you
1708 remembered to set \"-lmysqlclient"\ somewhere (e.g. in \\LOOKUP_LIBS\\)? You
1709 need that in order to get the MySQL library scanned when linking.
1710
1711
1712Q0110: I'm trying to build Exim with PAM support. I have included \"-lpam"\ in
1713 \\EXTRALIBS\\, but I'm still getting a linking error:
1714
1715==> /lib/libpam.so: undefined reference to `dlerror'
1716 /lib/libpam.so: undefined reference to `dlclose'
1717 /lib/libpam.so: undefined reference to `dlopen'
1718 /lib/libpam.so: undefined reference to `dlsym'
1719
1720A0110: Add \"-ldl"\ to \\EXTRALIBS\\. In some systems these dynamic loading functions
1721 are in their own library.
1722
1723
1724Q0111: I'm getting the error \*db.h: No such file or directory*\ when I try to
1725 build Exim.
1726
1727A0111: This problem has been seen with RedHat 7.0, but could also happen in
1728 other environments. If your system is using the DB library, you
1729 need to install the DB development package in order to build Exim.
1730 The package is called something like \"db3-devel-3.1.14-16.i386.rpm"\ for
1731 Linux systems, but you should check which version of DB you have
1732 installed (current releases are DB 4).
1733
1734
1735Q0112: I'm getting the error \*/usr/bin/ld: cannot find -ldb*\ when I try to
1736 build Exim.
1737
1738A0112: This is probably the same problem as Q0111.
1739
1740
1741Q0113: I've compiled Exim and I've managed to start it but there was one
1742 problem - it always complained that \(libmsqlclient.so.10)\ was not found,
1743 even though this file is in \(/usr/local/lib/mysql/)\.
1744
1745A0113: Solaris: ensure you have this in your \(Local/Makefile)\:
1746
1747==> LOOKUP_LIBS=-L/usr/local/lib/mysql -R/usr/local/lib/mysql
1748
1749 Net/Open/FreeBSD: Run this command (or ensure it gets run automatically
1750 at boot time):
1751
1752==> ldconfig -m /usr/local/lib/mysql
1753
1754 Linux: add \(/usr/local/lib/mysql)\ to \(/etc/ld.so.conf)\ and re-run \(ldconfig)\.
1755 Alternatively, add
1756
1757==> -Wl,-rpath -Wl,/usr/local/lib/mysql
1758
1759 to EXTRA_LIBS and then re-link (this is similar to the Solaris solution
1760 above). This will probably also work on other systems that use GNU
1761 Binutils.
1762
1763
1764Q0114: How can I remove Sendmail from my system? I've built Exim and run \"make
1765 install"\, but it still doesn't seem to be fully operational.
1766
1767A0114: If you are running FreeBSD, see Q9201. Otherwise, you need to arrange
1768 that whichever of the paths \(/usr/sbin/sendmail)\ or \(/usr/lib/sendmail)\
1769 exists on your system is changed to refer to Exim. For example, you
1770 could use these commands (as \/root/\):
1771
1772==> mv /usr/sbin/sendmail /usr/sbin/sendmail.original
1773 chmod u-s /usr/sbin/sendmail.original
1774 ln -s /path/to/exim /usr/sbin/sendmail
1775
1776 The second command removes the setuid privilege from the old MTA, as a
1777 general safety precaution. In the third command, substitute the actual
1778 path to the Exim binary for \(/path/to/exim)\.
1779
1780
1781Q0115: What does \*Can't open \(../scripts/newer)\: No such file or directory*\
1782 mean? I got it while trying to build Exim.
1783
1784A0115: You are using FreeBSD, or another OS that has a \^make^\ command which
1785 tries to optimize the running of commands. Exim's \(Makefile)\ contains
1786 targets with sequential commands like this:
1787
1788==> buildpcre:
1789 @cd pcre; $(MAKE) SHELL=$(SHELL) AR="$(AR)" $(MFLAGS) CC="$(CC)" \
1790 CFLAGS="$(CFLAGS) $(PCRE_CFLAGS)" \
1791 RANLIB="$(RANLIB)" HDRS="$(PHDRS)" \
1792 INCLUDE="$(INCLUDE) $(IPV6_INCLUDE) $(TLS_INCLUDE)"
1793 @if $(SHELL) $(SCRIPTS)/newer pcre/libpcre.a exim; then \
1794 /bin/rm -f exim eximon.bin; fi
1795
1796 The second command assumes that the \"cd pcre"\ in the first command is
1797 no longer in effect. If you have \"-j3"\ in your default set of
1798 \"MAKEFLAGS"\, FreeBSD \^make^\ tries to optimize, and ends up up with both
1799 commands in the same shell process. The result is that \"$(SCRIPTS)"\
1800 (which has a value of \"../scripts"\) is not found.
1801
1802 The simplest solution is to force \^make^\ to use backwards compatibility
1803 mode with each command in its own shell, by using the \-B\ flag. To
1804 ensure that this happens throughout the build, it's best to export it in
1805 your environment:
1806
f0884f39
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1807==> MAKEFLAGS='-B'
1808 export MAKEFLAGS
1809 make
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1810
1811
1812Q0116: I have tried to build Exim with Berkeley DB 3 and 4, but I always get
1813 errors.
1814
1815A0116: One common problem, especially when you have several different versions
1816 of BDB installed on the same host, is that the header files and library
1817 files for BDB are not in a standard place. You therefore need to tell
1818 Exim where they are, by setting INCLUDE and DBMLIB in your
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1819 \(Local/Makefile)\. For example, you could use this when you want to
1820 build with DB 4.1:
495ae4b0 1821
8e26e4bf
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1822==> INCLUDE=-I/usr/local/include/db-4.1
1823 DBMLIB=/usr/local/lib/db-4.1/libdb.a
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1824
1825 Specifying the complete library file like this will cause it to be
1826 statically linked with Exim. You'll have to check to see where these
1827 files are on your system. For example, on FreeBSD 5, the header is in
1828 \(/usr/local/include/db4)\ and the library is in \(/usr/local/lib)\ and
1829 called \(libdb4)\. In that environment, you could use:
1830
1831==> INCLUDE=-I/usr/local/include/db4
1832 DBMLIB=-L/usr/local/lib -ldb4
1833
1834 This time, DBMLIB is specifying the library directory (\(/usr/local/lib)\)
1835 and the name of the library (\(db4)\) separately. The name of the actual
1836 library file is \(/usr/local/lib/libdb4.something)\. If the library was
1837 compiled for dynamic linking, that will be used.
1838
1839
1840Q0117: Is there a quick walk-through of an Exim install from source anywhere?
1841
1842A0117: Here! This is a contribution from a RedHat user, somewhat edited. On
1843 other operating systems things may be slightly different, but the
1844 general approach is the same.
1845
1846 (1) Install the db needed for Exim. This needs to be done first if you
1847 don't have a DBM library installed. Go to \?http://www.sleepycat.com?\
1848 and download \(db-4.1.25.tar.gz)\, or whatever the current release is.
1849 Then:
1850
1851==> gunzip db-4.1.25.tar.gz
1852 tar -xvf db-4.1.25.tar
1853 cd db-4.1.25
1854 cd build_unix
1855 ../dist/configure
1856 make
1857 make install
1858
1859 (2) Add a user for use by Exim, unless you want to use an existing user
1860 such as \/mail/\:
1861
1862==> adduser exim
1863
77c27011 1864 (3) Now you can prepare to build Exim. Go to \?https://www.exim.org?\ or
20f0f788 1865 one of its mirrors, or the master FTP site
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1866 \?ftp://ftp.csx.cam.ac.uk/pub/software/email/exim/exim4?\, and download
1867 \(exim-4.20.tar.gz)\ or whatever the current release is. Then:
1868
1869==> gunzip exim-4.20.tar.gz
1870 tar -xvf exim-4.20.tar
1871 cd exim-4.20
1872 cp src/EDITME Local/Makefile
1873 cp exim_monitor/EDITME Local/eximon.conf
1874
1875 (4) Edit \(Local/Makefile)\:
1876
1877 Comment out EXIM_MONITOR= unless you want to install the Exim
1878 monitor (it requires X-windows).
1879
1880 Set the user you want Exim to use for itself:
1881
1882==> EXIM_USER=exim
1883
1884 If your DBM library is Berkeley DB, set up to use its native interface:
1885
1886==> USE_DB=yes
1887
1888 Make sure Exim's build can find the DBM library and its headers. If
1889 you've installed Berkeley DB 4 you'll need to have settings like this
1890 in \(Local/Makefile)\:
1891
1892==> INCLUDE=-I/usr/local/BerkeleyDB.4.1/include
1893 DBMLIB=/usr/local/BerkeleyDB.4.1/lib/libdb.a
1894
1895 (Check that the first directory contains the db.h file and that the
1896 second library exists.)
1897
1898 You don't need to change anything else, but you might want to review
1899 the default settings in the ``must specify'' section.
1900
1901 (4) Build Exim by running the \/make/\ command.
1902
1903 (5) Install Exim by running, as \/root/\:
1904
1905==> make install
1906
8e26e4bf 1907 You must be \/root/\ to do this. You do not have to be root for any of
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1908 the previous building activity.
1909
1910 (6) Run some tests on Exim; see if it will do local and remote
1911 deliveries. Change the configuration if necessary (for example,
1912 uncommenting \group\ on the \%local_delivery%\ transport if you don't
1913 use a ``sticky bit'' directory).
1914
1915 (7) Change Sendmail to Exim (of course you need to have had Sendmail
1916 installed to do this).
1917
1918==> /etc/init.d/sendmail stop
1919 mv /usr/sbin/sendmail /usr/sbin/sendmail.org
1920 ln -s /usr/exim/bin/exim /usr/sbin/sendmail
1921 /etc/init.d/sendmail start
1922
1923 (8) Check the Exim log. Either use the Exim monitor, or:
1924
1925==> tail -f /var/spool/exim/log/mainlog
1926
1927
1928Q0118: I've set \"LOOKUP_INCLUDE=-I/client/include"\ in Local/Makefile, but the
1929 compilation of \^exim_dumpdb^\ is ignoring this option and failing. Why?
1930
1931A0118: LOOKUP_INCLUDE is the special include file for lookup modules in Exim
1932 (e.g. mysql, LDAP). Confusingly, it doesn't apply to basic DBM code
1933 which is used also for other things. Try setting INCLUDE and DBMLIB
1934 instead. For example:
1935
1936==> USE_DB=yes
1937 INCLUDE=-I/client/include
1938 DBMLIB=/client/lib/libdb.a
1939
1940
1941Q0119: I know there are some 3rd-party patches for Exim, for exiscan and
1942 other things. Where are they?
1943
1944A0119: Exiscan is at \?http://duncanthrax.net/exiscan-acl/?\.
1945[[br]]
1946 Scanexi is at \?http://w1.231.telia.com/~u23107873/scanexi.html?\
1947[[br]]
1948 A sample \^^local_scan()^^\ function for interfacing to \^uvscan^\ is
1949 at \?http://www.dcs.qmul.ac.uk/~mb/local_scan/?\.
1950[[br]]
1951 An interface to SpamAssassin at SMTP time is at
1952 \?http://marc.merlins.org/linux/exim/sa.html?\.
1953[[br]]
1954 A mini-HOWTO (PDF file) about scanning and virus scanning, and some RPMs
1955 can be found at \?http://www.timj.co.uk/linux/exim.php?\.
1956
1957
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1958Q0120: I'm trying to compile with LOOKUP_WHOSON, but I keep getting \*In
1959 function `whoson_find': undefined reference to `wso_query'*\.
1960
1961A0120: Try adding \"-lwhoson"\ to your LOOKUP_LIBS setting in \(Local/Makefile)\.
1962
1963
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1964
19652. ROUTING IN GENERAL
1966
1967Q0201: How can I arrange that messages larger than some limit are handled by
1968 a special router?
1969
1970A0201: You can use a \condition\ option on the router line this:
1971
1972==> condition = ${if >{$message_size}{100K}{yes}{no}}
1973
1974
1975Q0202: Can I specify a list of domains to explicitly reject?
1976
1977A0202: Set up a named domain list containing the domains in the first section
1978 of the configuration, for example:
1979
1980==> domainlist reject_domains = list:of:domains:to:reject
1981
1982 You can use this list in an ACL to reject any SMTP recipients in those
1983 domains. You can also give a customized error message, like this:
1984
1985==> deny message = The domain $domain is no longer supported
1986 domains = +reject_domains
1987
1988 If you also want to reject these domains in messages that are submitted
1989 from the command line (not using SMTP), you need to set up a router to
1990 do it, like this:
1991
1992==> reject_domains:
1993 driver = redirect
1994 domains = +reject_domains
1995 allow_fail
1996 data = :fail: The domain $domain is no longer supported
1997
1998
1999Q0203: How can I arrange to do my own qualification of non-fully-qualified
2000 domains, and then pass them on to the next router?
2001
2002A0203: If you have some list of domains that you want to qualify, you can do
2003 this using a redirect router. For example,
2004
2005==> qualify:
2006 driver = redirect
2007 domains = *.a.b
2008 data = ${quote:$local_part}@$domain.c.com
2009
2010 This adds \".c.com"\ to any domain that matches \"*.a.b"\.
2011 If you want to do this in conjunction with a \%dnslookup%\ router, the
2012 \widen_domains\ option of that router may be another way of achieving
2013 what you want.
2014
2015
2016Q0204: Every system has a \"nobody"\ account under which httpd etc run. I would
2017 like to know how to restrict mail which comes from that account to users
2018 on that host only.
2019
2020A0204: Set up a first router like this:
2021
2022==> fail_nobody:
2023 driver = redirect
2024 senders = nobody@your.domain
2025 domains = ! +local_domains
2026 allow_fail
2027 data = :fail: Nobody may not mail off-site
2028
2029 This assumes you have defined \+local_domains\ as in the default
2030 configuration.
2031
2032
2033Q0205: How can I get Exim to deliver to me locally and everyone else at the same
2034 domain via SMTP to the MX record specified host?
2035
2036A0205: Create an \%accept%\ router to pick off the one address and pass it to
2037 an appropriate transport. Put this router before the one that does MX
2038 routing:
2039
2040==> me:
2041 driver = accept
2042 domains = dom.com
2043 local_parts = me
2044 transport = local_delivery
2045
2046 In the transport you will have to specify the \user\ option. An
2047 alternative way of doing this is to add a condition to the router that
2048 does MX lookups to make it skip your address. Subsequent routers can then
2049 deliver your address locally. You'll need a condition like this:
2050
2051==> condition = \
2052 ${if and {{eq{$domain}{dom.com}}{eq{$local_part}{me}}}{no}{yes}}
2053
2054
2055Q0206: How can I get Exim to deliver certain domains to a different SMTP port
2056 on my local host?
2057
2058A0206: You must set up a special \%smtp%\ transport, where you can specify the
2059 \port\ option, and then set up a router to route the domains to that
2060 transport. There are two possibilities for specifying the host:
2061
2062 (1) If you use a \%manualroute%\ router, you can specify the local host
2063 in the router options. You must also set
2064
2065==> self = send
2066
2067 so that it does not object to sending to the local host.
2068
2069 (2) If you use a router that cannot specify hosts (for example, an
2070 \%accept%\ router with appropriate conditions), you have to specify
2071 the host using the \hosts\ option of the transport. In this case,
2072 you must also set \allow_localhost\ on the transport.
2073
2074
2075Q0207: Why does Exim lower-case the local-part of a non-local domain when
2076 routing?
2077
2078A0207: Because \caseful_local_part\ is not set (in the default configuration)
2079 for the \%dnslookup%\ router. This does not matter because the local
2080 part takes no part in the routing, and the actual local part that is
2081 sent out in the RCPT command is always the original local part.
2082
2083
8e26e4bf
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2084Q0208: I can't get a lookup to work in a domain list. I'm trying this:
2085
2086==> domainlist local_domains = @:localhost:${lookup pgsql{SELECT ...
2087
2088A0208: Does the lookup return a colon separated list of domains? If not, you
2089 are using the wrong kind of lookup. The most common way of using a
2090 lookup in a domain list is something like this:
2091
2092==> domainlist local_domains = @:localhost:pgsql;SELECT ...
2093
2094 Using that syntax, if the query succeeds, the domain is considered to be
2095 in the list. The value that is returned is not relevant.
2096
2097
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2098
20993. ROUTING TO REMOTE HOSTS
2100
2101Q0301: What do \*lowest numbered MX record points to local host*\ and \*remote
2102 host address is the local host*\ mean?
2103
2104A0301: They mean exactly what they say. Exim expected to route an address to a
2105 remote host, but the IP address it obtained from a router was for the
2106 local host. If you really do want to send over TCP/IP to the local host
2107 (to a different version of Exim or another MTA, for example), see Q0206.
2108
2109 More commonly, these errors arise when Exim thinks it is routing some
2110 foreign domain. For example, the router configuration causes Exim to
2111 look up the domain in the DNS, but when Exim examines the DNS output,
2112 either the lowest numbered MX record points at the local host, or there
2113 are no MX records, and the address record for the domain contains an
2114 IP address that belongs to the local host.
2115
2116 There has been a rash of instances of domains being deliberately set up
2117 with MX records pointing to \"localhost"\ (or other names with A records
2118 that specify 127.0.0.1), which causes this behaviour. You can use the
2119 \ignore_target_hosts\ option to get Exim to ignore these records. The
4c04137d 2120 default configuration does this. For more discussion, see Q0319. For
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2121 other cases:
2122
2123 (1) If the domain is meant to be handled as a local domain, there
2124 is a problem with the configuration, because it should not then have
2125 been looked up in the DNS. Check the \domains\ settings on your
2126 routers.
2127
2128 (2) If the domain is one for which the local host is providing a
2129 relaying service (called ``mail hubbing''), possibly as part of a
2130 firewall, you need to set up a router to tell Exim where to send
2131 messages addressed to this domain, because the DNS directs them to
2132 the local host. You should put a router like this one before the one
2133 that does DNS lookups:
2134
2135==> hubbed_hosts:
2136 driver = manualroute
2137 transport = remote_smtp
2138 route_list = see discussion below
2139
2140 The contents of the \route_list\ option depend on how many hosts you
2141 are hubbing for, and how their names are related to the domain name.
2142 Suppose the local host is a firewall, and all the domains in
2143 \(*.foo.bar)\ have MX records pointing to it, and each domain
2144 corresponds to a host of the same name. Then the setting could be
2145
2146==> route_list = *.foo.bar $domain
2147
2148 If there isn't a convenient relationship between the domain names
2149 and the host names, you either have to list each domain separately,
2150 or use a lookup expansion to look up the host from the domain, or
2151 put the routing information in a file and use the \route_data\
2152 option with a lookup expansion.
2153
2154 (3) If neither (1) nor (2) is the case, the lowest numbered MX record or
2155 the address record for the domain should not be pointing to your
2156 host. You should arrange to get the DNS mended.
2157
2158
2159Q0302: Why does Exim say \*all relevant MX records point to non-existent hosts*\
2160 when MX records point to IP addresses?
2161
2162A0302: MX records cannot point to IP addresses. They are defined to point to
2163 host names, so Exim always interprets them that way. (An IP address is a
2164 syntactically valid host name.) The DNS for the domain you are having
2165 problems with is misconfigured.
2166
2167 However, it appears that more and more DNS zones are breaking the rules
2168 and putting IP addresses on the RHS of MX records. Exim follows the
2169 rules and rejects this, but other MTAs do support it, so the
2170 \allow_mx_to_ip\ was regretfully added at release 3.14 to permit this
2171 heinous activity.
2172
2173
2174Q0303: How do I configure Exim to send all messages to a central server? I
2175 don't want to do any local deliveries at all on this host.
2176
2177A0303: Use this as your first and only router:
2178
2179==> send_to_gateway:
2180 driver = manualroute
2181 transport = remote_smtp
2182 route_list = * central.server.host
2183
2184
2185Q0304: How do I configure Exim to send all non-local mail to a gateway host?
2186
2187A0304: Replace the \%dnslookup%\ router in the default configuration with the
2188 following:
2189
2190==> send_to_gateway:
2191 driver = manualroute
2192 domains = !+local_domains
2193 transport = remote_smtp
2194 route_list = * gate.way.host
2195
2196 If there are several hosts you can send to, you can specify them as a
2197 colon-separated list.
2198
2199
2200Q0305: How can I arrange for mail on my local network to be delivered directly
2201 to the relevant hosts, but all other mail to be sent to my ISP's mail
2202 server? The local hosts are all DNS-registered and behave like normal
2203 Internet hosts.
2204
2205A0305: Set up a first router to pick off all the domains for your local
2206 network. There are several ways you might do this. For example
2207
2208==> local_network:
2209 driver = dnslookup
2210 transport = remote_smtp
2211 domains = *.mydomain.com
2212
2213 This does a perfectly conventional DNS routing operation, but only for
2214 the domains that match \(*.mydomain.com)\. Follow this with a `smart
2215 host' router:
2216
2217==> internet:
2218 driver = manualroute
2219 domains = !+local_domains
2220 transport = remote_smtp
2221 route_list = * mail.isp.net
2222
2223 This routes any other non-local domains to the smart host.
2224
2225
2226Q0306: How do I configure Exim to send all non-local mail to a central server
2227 if it cannot be immediately delivered by my host? I don't want to have
2228 queued mail waiting on my host.
2229
2230A0306: Add to the \%remote_smtp%\ transport the following:
2231
2232==> fallback_hosts = central.server.name(s)
2233
2234 If there are several names, they must be separated by colons.
2235
2236
2237Q0307: The \route_list\ setting \"^foo$:^bar$ $domain"\ in a \%manualroute%\
2238 router does not work.
2239
2240A0307: The first thing in a \route_list\ item is a single pattern, not a list of
2241 patterns. You need to write that as \"^(foo|bar)$ $domain"\.
2242 Alternatively, you could use several items and write
2243
2244==> route_list = foo $domain; bar $domain
2245
2246 Note the semicolon separator. This is because the second thing in each
8e26e4bf 2247 item can itself be a colon-separated list of hosts.
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2248
2249
2250Q0308: I have a domain for which some local parts must be delivered locally,
2251 but the remainder are to be treated like any other remote addresses.
2252
2253A0308: One possible way of doing this is as follows: Assuming you are using a
2254 configuration that is similar to the default one, first exclude your
2255 domain from the first router by changing it to look like this:
2256
2257==> non_special_remote:
2258 driver = dnslookup
2259 domains = ! +local_domains : ! special.domain
2260 transport = remote_smtp
2261 ignore_target_hosts = 127.0.0.0/8
2262 no_more
2263
8e26e4bf 2264 Then add a second router to handle the local parts that are not to
495ae4b0
PH
2265 be delivered locally:
2266
2267==> special_remote:
2268 driver = dnslookup
2269 domains = special.domain
2270 local_parts = ! lsearch;/list/of/special/localparts
2271 transport = remote_smtp
2272 ignore_target_hosts = 127.0.0.0/8
2273 no_more
2274
2275 The remaining local parts will fall through to the remaining routers,
2276 which can delivery them locally.
2277
2278
2279Q0309: How can I configure Exim on a firewall machine so that if mail arrives
2280 addressed to a domain whose MX points to the firewall, it is forwarded
2281 to the internal mail server, without having to have a list of all the
2282 domains involved?
2283
2284A0309: As your first router, have the standard \%dnslookup%\ router from the
2285 default configuration, with the added option
2286
2287==> self = pass
2288
2289 This will handle all domains whose lowest numbered MX records do not
2290 point to your host. Because of the \no_more\ setting, if it encounters
2291 an unknown domain, routing will fail. However, if it hits a domain whose
2292 lowest numbered MX points to your host, the \self\ option comes into
2293 play, and overrides \no_more\. The \"pass"\ setting causes it to pass
2294 the address on to the next router. (The default causes it to generate an
2295 error.)
2296
2297 The only non-local domains that reach the second router are those with
2298 MX records pointing to the local host. Set it up to send them to the
2299 internal mail server like this:
2300
2301==> internal:
2302 driver = manualroute
2303 domains = ! +local_domains
2304 transport = remote_smtp
2305 route_list = * internal.server
2306
2307
2308Q0310: If a DNS lookup returns no MX records why doesn't Exim just bin the
2309 message?
2310
2311A0310: If a DNS lookup returns no MXs, Exim looks for an address record, in
2312 accordance with the rules that are defined in the RFCs. If you want to
2313 break the rules, you can set \mx_domains\ in the \%dnslookup%\ router, but
2314 you will cut yourself off from those sites (and there still seem to be
2315 plenty) who do not set up MX records.
2316
2317
2318Q0311: When a DNS lookup for MX records fails to complete, why doesn't Exim
85ffcba6 2319 send the message to the host defined by the A record?
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2320
2321A0311: The RFCs are quite clear on this. Only if it is known that there are no
2322 MX records is an MTA allowed to make use of the A record. When an MX
2323 lookup fails to complete, Exim does not know whether there are any MX
2324 records or not. There seem to be some name servers (or some
2325 configurations of some name servers) that give a ``server fail'' error when
2326 asked for a non-existent MX record. Exim uses standard resolver calls,
2327 which unfortunately do not distinguish between this case and a timeout,
2328 so all Exim can do is try again later.
2329
2330
2331Q0312: Is it possible to use a conditional expression for the host item in a
2332 \route_list\ for \%manualroute%\ router? I tried the following, but it
2333 doesn't work:
2334
2335==> route_list = * ${if match{$header_from:}{\N.*\.usa\.net$\N} \
2336 {<smarthost1>}{<smarthost2>}
2337
2338A0312: The problem is that the second item in \route_list\ contains white
2339 space, which means that it gets terminated prematurely. To avoid this,
2340 you must put the second item in quotes:
2341
2342==> route_list = * "${if match{$header_from:}{\N.*\.usa\.net$\N} \
2343 {<smarthost1>}{<smarthost2>}}"
2344
2345
2346Q0313: I send all external mail to a smart host, but this means that bad
2347 addresses also get passed to the smart host. Can I avoid this?
2348
2349A0313: Assuming you have DNS availability, set up a conventional \%dnslookup%\
2350 router to do the routing, but in the \%remote_smtp%\ transport set this:
2351
2352==> hosts = your.smart.host
2353 hosts_override
2354
2355 This will override the hosts that the router finds so that everything
2356 goes to the smart host, but any non-existent domains will be failed by
2357 the router.
2358
2359
2360Q0314: I have a really annoying intermittent problem where attempts to mail to
2361 valid sites are rejected with \*unknown mail domain*\. This only happens a
2362 few times a day and there is no particular pattern to the sites it
2363 rejects. If I try to lookup the same domain a few minutes later then it
2364 is OK.
2365
2366A0314: This is almost certainly a problem with the DNS resolver or the the
2367 domain's name servers.
2368
2369 (1) Have you linked Exim against the newest DNS resolver library that
2370 comes with Bind? If you are using SunOS4 that may be your problem, as
2371 the resolver that comes with that OS is known to be buggy and to give
2372 intermittent false negatives.
2373
2374 (2) Effects like this are sometimes seen if a domain's name servers get
2375 out of step with each other.
2376
2377
2378Q0315: I'd like route all mail with addresses that can't be resolved (the DNS
2379 lookup times out) to a relay machine.
2380
2381A0315: Set \pass_on_timeout\ on your \%dnslookup%\ router, and add below it a
2382 \%manualroute%\ router that routes all relevant domains to the relay.
2383
2384
2385Q0316: I would like to forward all incoming email for a particular domain to
2386 another host via SMTP. Whereabouts would I configure that?
2387
2388A0316: Use this as your first router:
2389
2390==> special:
2391 driver = manualroute
2392 transport = remote_smtp
2393 route_list = the.particular.domain the.other.host
2394
2395 You will also need to adjust the ACL for incoming SMTP so that this
2396 domain is accepted for relaying. If you are using the default
2397 configuration, there is a domain list called \relay_domains\ that is
2398 set up for this.
2399
2400
2401Q0317: What I'd like to do is have alternative smart hosts, where the one to be
2402 used is determined by which ISP I'm connected to.
2403
2404A0317: The simplest way to do this is to arrange for the name of the smart host
2405 du jour to be placed in a file when you connect, say \(/etc/smarthost)\.
2406 Then you can read this file from a \%manualroute%\ router like this:
2407
2408==> smarthost:
2409 driver = manualroute
2410 transport = remote_smtp
2411 route_list = * ${readfile{/etc/smarthost}{}}
2412
2413 The second argument of the \"readfile"\ item is a string that replaces
2414 any newline characters in the file (in this case, with nothing).
2415 By keeping the data out of the main configuration file, you avoid having
2416 to HUP the daemon when it changes.
2417
2418
2419Q0318: Exim won't route to a host with no MX record.
2420
2421A0318: More than one thing may cause this.
2422
2423 (1) Are you sure there really is no MX record? Sometimes a typo results
2424 in a malformed MX record in the zone file, in which case some name
2425 servers give a SERVFAIL error rather than NXDOMAIN. Exim has to treat
2426 this as a temporary error, so it can't go on to look for address records.
2427 You can check for this state using one of the DNS interrogation commands,
2428 such as \(nslookup)\, \(host)\, or \(dig)\.
2429
2430 (2) Is there a wildcard MX record for \(your)\ domain? Is the
2431 \search_parents\ option on in your \%dnslookup%\ router? If the answer to
2432 both these questions is ``yes'', that is the cause of the problem. When
2433 the DNS resolver fails to find the MX record, it tries adding on your
2434 domain if \search_parents\ is true, and thereby finds your wildcard MX
2435 record. For example:
2436
2437 . There is a wildcard MX record for \(*.a.b.c)\.
2438
2439 . There is a host called \(x.y.z)\ that has an A record and no MX record.
2440
2441 . Somebody on the host \(m.a.b.c)\ domain tries to mail to \(user@x.y.z)\.
2442
2443 . Exim calls the DNS to look for an MX record for \(x.y.z)\.
2444
2445 . The DNS doesn't find any MX record. Because \search_parents\ is true,
2446 it then tries searching the current host's parent domain, so it
2447 looks for \(x.y.z.a.b.c)\ and picks up the wildcard MX record.
2448
2449 Setting \search_parents\ false makes this case work while retaining the
2450 wildcard MX record. However, anybody on the host \(m.a.b.c)\ who mails to
2451 \(user@n.a)\ (expecting it to go to \(user@n.a.b.c)\) now has a problem. The
2452 \widen_domains\ option of the \%dnslookup%\ router may be helpful in this
2453 circumstance.
2454
2455
2456Q0319: I have some mails on my queues that are sticking around longer than
2457 the retry time indicates they should. They are all getting frozen
2458 because some remote admin has set their MX record to 127.0.0.1.
2459
2460A0319: The admin in question is an idiot. Exim will always freeze such messages
2461 because they are apparently routed to the local host. To bounce these
2462 messages immediately, set
2463
2464==> ignore_target_hosts = 127.0.0.1
2465
2466 on the \%dnslookup%\ router. This causes Exim to completely ignore any hosts
2467 with that IP address. In fact, there are quite a number of IP addresses
2468 that should never be used. Here is a suggested configuration list for
2469 the IPv4 ones:
2470
2471==> # Don't allow domains whose single MX (or A) record is a
2472 # "special-use IPv4 address", as listed in RFC 3330.
2473 ignore_target_hosts = \
f0884f39
PH
2474 # Hosts on "this network"; RFC 1700 (page 4) states that these
2475 # are only allowed as source addresses
2476 0.0.0.0/8 : \
2477 # Private networks, RFC 1918
2478 10.0.0.0/8 : 172.16.0.0/12 : 192.168.0.0/16 : \
2479 # Internet host loopback address, RFC 1700 (page 5)
2480 127.0.0.0/8 : \
2481 # "Link local" block
2482 169.254.0.0/16 : \
2483 # "TEST-NET" - should not appear on the public Internet
2484 192.0.2.0/24 : \
2485 # 6to4 relay anycast addresses, RFC 3068
2486 192.88.99.0/24 : \
2487 # Network interconnect device benchmark testing, RFC 2544
2488 198.18.0.0/15 : \
2489 # Multicast addresses, RFC 3171
2490 224.0.0.0/4 : \
2491 # Reserved for future use, RFC 1700 (page 4)
2492 240.0.0.0/4
495ae4b0
PH
2493
2494
2495Q0320: How can I arrange for all mail to \*user@some.domain*\ to be forwarded
2496 to \*user@other.domain*\?
2497
2498A0320: Put this as your first router:
2499
2500==> forward:
2501 driver = redirect
2502 domains = some.domain
2503 data = ${quote:$local_part}@other.domain
2504
2505
2506Q0321: How can I tell an Exim router to use only IPv4 or only IPv6 addresses
2507 when it finds both types in the DNS?
2508
2509A0321: You can do this by making it ignore the addresses you don't want. This
2510 example ignores all IPv6 addresses and all IPv4 addresses in the 127
2511 network:
2512
2513==> ignore_target_hosts = <; 0000::0000/0 ; 127.0.0.0/8
2514
2515 To ignore all IPv4 addresses, use
2516
2517==> ignore_target_hosts = 0.0.0.0/0
2518
2519 See Q0319 for a general discussion of \ignore_target_hosts\.
2520
2521
2522Q0322: How can I reroute all messages bound for 192.168.10.0 and 10.0.0.0 to
2523 a specific mail server?
2524
2525A0322: That is an odd requirement. However, there is an obscure feature in
2526 Exim, originally implemented for packet radio people, that perhaps can
2527 help. Check out the \translate_ip_address\ generic router option.
2528
2529
2530
25314. ROUTING FOR LOCAL DELIVERY
2532
2533Q0401: I need to have any mail for \(virt.dom.ain)\ that doesn't match one of the
2534 aliases in \(/usr/lib/aliases.virt)\ delivered to a particular address, for
2535 example, \(postmaster@virt.dom.ain)\.
2536
2537A0401: Adding an asterisk to a search type causes Exim to look up ``*'' when the
2538 normal lookup fails. So if your aliasing router is something like this:
2539
2540==> virtual:
2541 driver = redirect
2542 domains = virt.dom.ain
2543 data = ${lookup{$local_part}lsearch{/usr/lib/aliases.virt}}
2544 no_more
2545
2546 you should change \"lsearch"\ to \"lsearch*"\, and put this in the alias
2547 file:
2548
2549==> *: postmaster@virt.dom.ain
2550
2551 This solution has the feature that if there are several unknown
2552 addresses in the same message, only one copy gets sent to the
2553 postmaster, because of Exim's normal de-duplication rules.
2554
2555 NOTE: This solution works only if there is also an entry for \(postmaster)\
2556 in the alias file, ultimately resolving to an address that is not in
2557 \(virt.dom.ain)\. See also Q0434.
2558
2559
2560Q0402: How do I arrange for all incoming email for \(*@some.domain)\ to go into one
2561 pop3 mail account? The customer doesn't want to add a list of specific
2562 local parts to the system.
2563
2564A0402: Set up a special transport that writes to the mailbox like this:
2565
2566==> special_transport:
2567 driver = appendfile
2568 file = /pop/mailbox
2569 envelope_to_add
2570 return_path_add
2571 delivery_date_add
2572 user = exim
2573
2574 The file will be written as the user \"exim"\. Then arrange to route all
2575 mail for that domain to that transport, with a router like this:
2576
2577==> special_router:
2578 driver = accept
2579 domains = some.domain
2580 transport = special_transport
2581
2582
2583Q0403: How do I configure Exim to send messages for unknown local users to a
2584 central server?
2585
2586A0403: Assuming you are using something like the default configuration, where
2587 local users are processed by the later routers, you should add the
2588 following router at the end:
2589
2590==> unknown:
2591 driver = manualroute
2592 transport = remote_smtp
2593 route_list = * server.host.name
2594 no_verify
2595
2596 However, you should if possible try to verify that the user is known on
2597 the central server before accepting the message in the first place. This
2598 can be done by making use of Exim's ``call forward'' facility.
2599
2600
2601Q0404: How can I arrange for messages submitted by (for example) Majordomo to
2602 be handled specially?
2603
2604A0404: You can use the \condition\ option on a router, with a setting such as
2605
2606==> condition = ${if and {{eq {$sender_host_address}{}} \
2607 {eq {$sender_ident}{majordom}}} {yes}{no}}
2608
2609 This first tests for a locally-submitted message, by ensuring there is
2610 no sending host address, and then it checks the identity of the user
2611 that ran the submitting process.
2612
2613
2614Q0405: On a host that accepts mail for several domains, do I have to use fully
2615 qualified addresses in \(/etc/aliases)\ or do I have to set up an alias
2616 file for each domain?
2617
2618A0405: You can do it either way. The default aliasing router contains this line:
2619
2620==> data = ${lookup{$local_part}lsearch{/etc/aliases}}
2621
2622 which is what does the actual lookup. To make it look up the complete
2623 address instead of just the local part, use
2624
2625==> data = ${lookup{$local_part@$domain}lsearch{/etc/aliases}}
2626
2627 If you want to use a separate file for each domain, use
2628
2629==> data = ${lookup{$local_part}lsearch{/etc/aliases/$domain}}
2630
2631
2632Q0406: Some of my users are using the \(.forward)\ to pipe to a shell command which
2633 appends to the user's INBOX. How can I forbid this?
2634
2635A0406: If you allow your users to run shells in pipes, you cannot control which
2636 commands they run or which files they write to. However, you should point
2637 out to them that writing to an INBOX by arbitrary commands is not
2638 interlocked with the MTA and MUAs, and is liable to mess up the contents
2639 of the file.
2640
2641 If a user simply wants to choose a specific file for the delivery of
2642 messages, this can be done by putting a file name in a \(.forward)\ file
2643 rather than using a pipe, or by using the \"save"\ command in an Exim
2644 filter file.
2645
2646 You can set \forbid_pipe\ on the router, but that will prevent them from
2647 running any pipe commands at all. Alternatively, you can restrict which
2648 commands they may run in their pipes by setting the \allow_commands\
2649 and/or \restrict_to_path\ options in the \%address_pipe%\ transport.
2650
2651
2652Q0407: How can I arrange for a default value when using a query-style lookup
2653 such as LDAP or NIS+ to handle aliases?
2654
2655A0407: Use a second query in the failure part of the original lookup, like
2656 this:
2657
2658==> data = ${lookup ldap\
2659 {ldap://x.y.z/l=yvr?aliasaddress?sub?(&(mail=$local_part@$domain))}\
2660 {$value}\
2661 {\
2662 ${lookup ldap \
2663 {ldap://x.y.z/l=yvr?aliasaddress?sub?(&(mail=default@$domain))}}\
2664 }}
2665
2666 Of course, if the default is a fixed value you can just include it
2667 directly.
2668
2669
2670Q0408: If I don't fully qualify the addresses in a virtual domain's alias file
2671 then mail to aliases which also match the local domain get delivered to
2672 the local domain.
2673
2674A0408: Set the \qualify_preserve_domain\ option on the \%redirect%\ router.
2675
2676
2677Q0409: I want mail for any local part at certain virtual domains to go
2678 to a single address for each domain.
2679
9c2b45c9 2680A0409: One way to do this is
495ae4b0
PH
2681
2682==> virtual:
2683 driver = redirect
2684 data = ${lookup{$domain}lsearch{/etc/virtual}}
2685
2686 The \(/etc/virtual)\ file contains a list of domains and the addresses to
2687 which their mail should be sent. For example:
2688
2689==> domain1: postmaster@some.where.else
2690 domain2: joe@xyz.plc
2691
2692 If the number of domains is large, using a DBM or cdb file would be more
2693 efficient. If the lookup fails to find the domain in the file, the value
2694 of the \data\ option is empty, causing the router to decline.
2695
2696
2697Q0410: How can I make Exim look in the alias NIS map instead of \(/etc/aliases)\?
2698
2699A0410: The default configuration does not use NIS (many hosts don't run it).
2700 You need to change this line in the \%system_aliases%\ router:
2701
2702==> data = ${lookup{$local_part}lsearch{/etc/aliases}}
2703
2704 Change it to
2705
2706==> data = ${lookup{$local_part}nis{mail.aliases}}
2707
2708 If you want to use \(/etc/aliases)\ as well as NIS, put this router (with
2709 a different name) before or after the default one, depending on which
2710 data source you want to take precedence.
2711
2712
2713Q0411: Why will Exim deliver a message locally to any username that is longer
2714 than 8 characters as long as the first 8 characters match one of the
2715 local usernames?
2716
2717A0411: The problem is in your operating system. Exim just calls the \^^getpwnam()^^\
2718 function to test a local part for being a local login name. It does not
2719 presume to guess the maximum length of user name for the underlying
2720 operating system. Many operating systems correctly reject names that are
2721 longer than the maximum length; yours is apparently deficient in this
2722 regard. To cope with such systems, Exim has an option called
2723 \max_user_name_length\ which you can set to the maximum allowed length.
2724
2725
2726Q0412: Why am I seeing the error \*bad mode (100664) for /home/test/.forward*\?
2727 I've looked through the documentation but can't see anything to suggest
2728 that Exim has to do anything other than read the \(.forward)\ file.
2729
2730A0412: For security, Exim checks for mode bits that shouldn't be set, by
2731 default 022. You can change this by setting the \modemask\ option of the
2732 \%redirect%\ router that is handling \(.forward)\ files.
2733
2734
2735Q0413: When a user's \(.forward)\ file is syntactially invalid, Exim defers
2736 delivery of all messages to that user, which sometimes include the
2737 user's own test messages. Can it be told to ignore the \(.forward)\ file
2738 and/or inform the user of the error?
2739
2740A0413: Setting \skip_syntax_errors\ on the redirect router causes syntax
2741 errors to be skipped. When dealing with users' \(.forward)\ files it is best
2742 to combine this with a setting of \syntax_errors_to\ in order to send
2743 a message about the error to the user. However, to avoid an infinite
2744 cascade of messages, you have to be able to send to an address that
2745 bypasses \(.forward)\ file processing. This can be done by including a
2746 router like this one
2747
2748==> real_localuser:
2749 driver = accept
2750 check_local_user
2751 transport = local_delivery
90af77f4 2752 local_part_prefix = real-
495ae4b0
PH
2753
2754 before the \%redirect%\ router that handles \(.forward)\ files. This will
2755 do an ordinary local delivery without \(.forward)\ processing, if the
2756 local part is prefixed by \"real-"\. You can then set something like
2757 the following options on the \%redirect%\ router:
2758
2759==> skip_syntax_errors
2760 syntax_errors_to = real-$local_part@$domain
2761 syntax_errors_text = "\
2762 This is an automatically generated message. An error has been \
2763 found\nin your .forward file. Details of the error are reported \
2764 below. While\nthis error persists, messages addressed to you will \
2765 get delivered into\nyour normal mailbox and you will receive a \
2766 copy of this message for\neach one."
2767
2768 A final tidying setting to go with this is a rewriting rule that changes
2769 \"real-username"\ into just \"username"\ in the headers of the message:
2770
2771==> \N^real-([^@]+)@your\.dom\.ain$\N $1@your.dom.ain h
2772
2773 This means that users won't ever see the \"real-"\ prefix, unless they
2774 look at the ::Envelope-To:: header.
2775
2776
2777Q0414: I have set \caseful_local_part\ on the routers that handle my local
2778 domain because my users have upper case letters in their login names,
2779 but incoming mail now has to use the correct case. Can I relax this
2780 somehow?
2781
2782A0414: If you really have to live with caseful user names but want incoming
2783 local parts to be caseless, then you have to maintain a file, indexed by
2784 the lower case forms, that gives the correct case for each login, like
2785 this:
2786
2787==> admin: Admin
2788 steven: Steven
2789 mcdonald: McDonald
2790 lamanch: LaManche
2791 ...
2792
2793 and at the start of the routers that handle your local domain, put one
2794 like this:
2795
2796==> set_case_router:
2797 driver = redirect
2798 data = ${lookup{${lc:$local_part}}lsearch{/the/file}}
2799 qualify_preserve_domain
2800
2801 For efficiency, you should also set the \redirect_router\ option to cause
2802 processing of the changed address to begin at the next router. If you
2803 are otherwise using the default configuration, the setting would be
2804
2805==> redirect_router = system_aliases
2806
2807 If there are lots of users, then a DBM or cdb file would be more
2808 efficient than a linear search. If you are handling several domains,
2809 you will have to extend this configuration to cope appropriately.
2810
2811
2812Q0415: Can I use my existing alias files and forward files as well as procmail
2813 and effectively drop in Exim in place of Sendmail ?
2814
2815A0415: Yes, as long as your alias and forward files don't assume that pipes are
2816 going to run under a shell. If they do, you either have to change them,
2817 or configure Exim to use a shell (which it doesn't by default).
2818
2819
2820Q0416: What is quickest way to set up Exim so any message sent to a
2821 non-existing user would bounce back with a different message, based
2822 on the name of non-existing user?
2823
2824A0416: Place this router last, so that it catches any local addresses that
2825 are not otherwise handled:
2826
2827==> non_exist:
2828 driver = accept
2829 transport = non_exist_reply
2830 no_verify
2831
2832 Then add the following transport to the transports section:
2833
2834==> non_exist_reply:
2835 driver = autoreply
2836 user = exim
2837 to = $sender_address
2838 subject = User does not exist
2839 text = You sent mail to $local_part. That's not a valid user here. \
2840 The subject was: $subject.
2841
2842 If you want to pick up a message from a file, you can use the \file\
2843 option (use \file_expand\ if you want its contents expanded).
2844
2845
2846Q0417: What do I need to do to make Exim handle \(/usr/ucb/vacation)\ processing
2847 automatically, so that people could just create a \(.vacation.msg)\ file in
2848 their home directory and not have to edit their \(.forward)\ file?
2849
2850A0417: Add a new router like this, immediately before the normal \%localuser%\
2851 router:
2852
2853==> vacation:
2854 driver = accept
2855 check_local_user
2856 require_files = $home/.vacation.msg
2857 transport = vacation_transport
2858 unseen
2859
2860 and a matching new transport like this:
2861
2862==> vacation_transport:
2863 driver = pipe
2864 command = /usr/ucb/vacation $local_part
2865
2866 However, some versions of \(/usr/ucb/vacation)\ do not work properly unless
2867 the DBM file(s) it uses are created in advance - it won't create them
2868 itself. You also need a way of removing them when the vacation is over.
2869
2870 Another possibility is to use a fixed filter file which is run whenever
2871 \(.vacation.msg)\ exists, for example:
2872
2873==> vacation:
2874 driver = redirect
2875 check_local_user
2876 require_files = $home/.vacation.msg
2877 file = /some/central/filter
2878 allow_filter
2879
2880 The filter file should use the \"if personal"\ check before sending mail,
2881 to avoid generating automatic responses to mailing lists. If sending a
2882 message is all that it does, this doesn't count as a ``significant''
2883 delivery, so the original message goes on to be delivered as normal.
2884
2885 Yet another possibility is to make use of Exim's \%autoreply%\ transport,
2886 and not use \(/usr/ucb/vacation)\ at all.
2887
2888
2889Q0418: I want to use a default entry in my alias file to handle unknown local
2890 parts, but it picks up the local parts that the aliases generate. For
2891 example, if the alias file is
2892
2893==> luke.skywalker: luke
2894 ls: luke
2895 *: postmaster
2896
2897 then messages addressed to \/luke.skywalker/\ end up at \/postmaster/\.
2898
2899A0418: The default mechanism works best with virtual domains, where the
2900 generated address is not in the same domain. If you just want to pick up
2901 all unknown local parts and send them to postmaster, an easier way to do
2902 it is to put this as your last router:
2903
2904==> unknown:
2905 driver = redirect
2906 data = postmaster
2907 no_verify
2908
2909 Another possibility is to put the redirect router for these aliases
2910 after all the other routers, so that local parts which are user names
2911 get picked off first. You will need to have two aliasing routers if
2912 there are some local parts (e.g. \/root/\) which are login names, but which
2913 you want to handle as aliases.
2914
2915
2916Q0419: I have some obsolete domains which people have been warned not to use
2917 any more. How can I arrange to delete any mail that is sent to them?
2918
2919A0419: To reject them at SMTP time, with a customized error message, place
aded2255 2920 statements like this in the ACL:
495ae4b0
PH
2921
2922==> deny message = The domain $domain is obsolete
2923 domains = lsearch;/etc/exim/obsolete.domains
2924
2925 For messages that don't arrive over SMTP, you can use a router like
2926 this to bounce them:
2927
2928==> obsolete:
2929 driver = redirect
2930 domains = lsearch;/etc/exim/obsolete.domains
2931 allow_fail
2932 data = :fail: the domain $domain is obsolete
2933
2934 If you just want to throw away mail to those domains, accept them at
2935 SMTP time, and use a router like this:
2936
2937==> obsolete:
2938 domains = lsearch;/etc/exim/obsolete.domains
2939 data = :blackhole:
2940
2941
2942Q0420: How can I arrange that mail addressed to \(anything@something.mydomain.com)\
2943 gets delivered to \(something@mydomain.com)\?
2944
2945A0420: Set up a router like this:
2946
2947==> user_from_domain:
2948 driver = redirect
2949 data = ${if match{$domain}{\N^(.+)\.mydomain\.com$\N}\
2950 {$1@mydomain.com}}
2951
2952
2953Q0421: I can't get a regular expression to work in a \local_parts\ option on
2954 one of my routers.
2955
2956A0421: Have you remembered to protect any backslash and dollar characters in
2957 your regex from unwanted expansion? The easiest way is to use the
2958 \"@\N"\ facility, like this:
2959
2960==> local_parts = \N^0740\d{6}\N
2961
2962
2963Q0422: How can I arrange for all addresses in a group of domains \(*.example.com)\
2964 to share the same alias file? I have a number of such groups.
2965
2966A0422: For a single group you could just hard wire the file name into a router
2967 that had
2968
2969==> domains = *.example.com
2970
2971 set, to restrict it to the relevant domains. For a number of such groups
2972 you can create a file containing the domains, like this:
2973
2974==> *.example1.com example1.com
2975 *.example2.com example2.com
2976 ...
2977
2978 Then create a router like this
2979
2980==> domain_aliases:
2981 driver = redirect
2982 domains = partial-lsearch;/that/file
2983 data = ${lookup{$local_part}lsearch*{/etc/aliases.d/$domain_data}}
2984
2985 The variable \$domain_data$\ contains the data that was looked up when the
2986 \domains\ option was matched, i.e. \"example1.com"\, \"example2.com"\, etc.
2987 in this case.
2988
2989
2990Q0423: Some of our users have no home directories; the field in the password
2991 file contains \(/no/home/dir)\. This causes the error \*failed to stat
2992 /no/home/dir (No such file or directory)*\ when Exim tries to look for a
2993 \(.forward file)\, and the delivery is deferred.
2994
2995A0423: There are two issues involved here:
2996
2997 (1) With the default configuration, you are asking Exim to check for a
2998 \(.forward)\ file in the user's home directory. If no file is found,
2999 Exim tries to \^^stat()^^\ the home directory. This is so that it will
3000 notice a missing NFS home directory, and not treat it as if the
3001 \(.forward)\ file did not exist. This \^^stat()^^\ is failing when the
3002 home directory really doesn't exist. You should arrange for the
3003 \%userforward%\ router not to run for these special users, by adding
3004 this line:
3005
3006==> condition = ${if eq {$home}{/no/home/dir}{no}{yes}}
3007
3008 (2) If you use \check_local_user\ on another router to route to a local
3009 transport (again, this is what is in the default configuration), you
3010 will also have to specify a current directory for the transport, because
3011 by default it makes the home directory current. This is easily done by
3012 adding
3013
3014==> current_directory = /
3015
3016 to the transport or
3017
3018==> transport_current_directory = /
3019
3020 to the router. Or you can add \home_directory\ to the transport, because
3021 the current directory defaults to the home directory.
3022
3023
3024Q0424: How can I disable Exim's de-duplication features? I want it to do two
3025 deliveries if two different aliases expand to the same address.
3026
3027A0424: This is not possible. Duplication has other ramifications other than
3028 just (in)convenience. Consider:
3029
3030 . Message is addressed to A and to B.
3031
3032 . Both A and B are aliased to C.
3033
3034 . Without de-duplication, two deliveries to C are scheduled.
3035
3036 . One delivery happens, Exim records that it has delivered the message
3037 to C.
3038
3039 . The next delivery fails (C's mailbox is over quota, say).
3040
3041 Next time round, Exim wants to know if it has already delivered to C or
3042 not, before scheduling a new delivery. Has it? Obviously, if duplicate
3043 deliveries are supported, it has to remember not only that it has
3044 delivered to C but also the ``history'' of how that delivery happened - in
3045 effect an ancestry list back to the original envelope address. This it
3046 does not do, and changing it to work in that way would be a lot of work
3047 and a big upheaval.
3048
3049 The best way to get duplicate deliveries if you want them is not to use
3050 aliases, but to route the addresses directly to a transport, e.g.
3051
3052==> duplicates:
3053 driver = accept
3054 local_parts = lsearch;/etc/list/of/special/local/parts
3055 transport = local_delivery
3056 user = exim
3057
3058
3059Q0425: My users' mailboxes are distributed between several servers according to
3060 the first letter of the user name. All the servers receive incoming mail
3061 at random. I would like to have the same configuration file for all the
3062 servers, which does local delivery for the mailboxes it holds, and sends
3063 other addresses to the correct other server. Is this possible?
3064
3065A0425: It is easiest if you arrange for all the users to have password entries
3066 on all the servers. This means that non-existent users can be detected
3067 at the first server they reach. Set up a file containing a mapping from
3068 the first letter of the user names to the servers where their mailboxes
3069 are held. For example:
3070
3071==> a: server1
3072 b: server1
3073 c: server2
3074 ...
3075
3076 Before the normal \%localuser%\ router, place the following router:
3077
3078==> mailbox_host:
3079 driver = manualroute
3080 check_local_user
3081 transport = remote_smtp
3082 route_list = * ${lookup{${substr_0_1:$local_part}}lsearch{/etc/mapfile}}
3083 self = pass
3084
3085 This router checks for a local account, then looks up the host from the
3086 first character of the local part. If the host is not the local host,
3087 the address is routed to the \%remote_smtp%\ transport, and sent to the
3088 correct host. If the host is the local host, the \self\ option causes
3089 the router to pass the address to the next router, which does a local
3090 delivery.
3091
3092 The router is skipped for local parts that are not the names of local
3093 users, and so these addresses fail.
3094
3095
3096Q0426: One of the things I want to set up is for \(anything@onedomain)\ to forward
3097 to \(anything@anotherdomain)\. I tried adding \($local_part@anotherdomain)\ to
3098 my aliases but it did not expand - it sent it to that literal address.
3099
3100A0426: If you want to do it that way, you can use the \"expand"\ operator on
3101 the lookup used in the data option of the redirect router. For example:
3102
3103==> data = ${expand:${lookup{$local_part}lsearch*{/etc/aliases}}}
3104
3105 Another approach is to use a router like this:
3106
3107==> forwarddomain:
3108 driver = redirect
3109 domains = onedomain
3110 data = $local_part@anotherdomain
3111
3112 The value of \data\ can, of course, be more complicated, involving
3113 lookups etc. if you have lots of different cases.
3114
3115
3116Q0427: How can I have an address looked up in two different alias files, and
3117 delivered to all the addresses that are found?
3118
3119A0427: Use a router like this:
3120
3121==> multi_aliases:
3122 driver = redirect
3123 data = ${lookup{$local_part}lsearch{/etc/aliases1}\
3124 {$value${lookup{$local_part}lsearch{/etc/aliases2}{,$value}}}\
3125 {${lookup{$local_part}lsearch{/etc/aliases2}{$value}fail}}}\
3126
3127 If the first lookup succeeds, the result is its data, followed by the
3128 data from the second lookup, if any, separated by a comma. If the first
3129 lookup fails, the result is the data from the third lookup (which also
3130 looks in the second file), but if this also fails, the entire expansion
3131 is forced to fail, thereby causing the router to decline.
3132
3133 Another approach is to use two routers, with the first re-generating the
3134 original local part when it succeeds. This won't get processed by the
3135 same router again. For example:
3136
3137==> multi_aliases1:
3138 driver = redirect
3139 data = ${lookup{$local_part}lsearch{/etc/aliases1}{$value,$local_part}}
3140
3141==> multi_aliases2:
3142 data = ${lookup{$local_part}lsearch{/etc/aliases2}}
3143
3144 This scales more easily to three or more alias files.
3145
3146
3147Q0428: I've converted from Sendmail, and I notice that Exim doesn't make use
3148 of the \"owner-"\ entries in my alias file to change the sender address in
3149 outgoing messages to a mailing list.
3150
3151A0428: If you have an alias file with entries like this:
3152
3153==> somelist: a@b, c@d, ...
3154 owner-somelist: postmaster
3155
3156 Sendmail assumes that the second entry specifies a new sender address
3157 for the first. Exim does not make this assumption. However, you can make
3158 it take the same action, by adding
3159
3160==> errors_to = owner-$local_part@whatever.domain
3161
3162 to the configuration for your aliasing router. This is fail-safe,
3163 because Exim verifies a new sender address before using it. Thus, the
3164 change of sender address occurs only when the owner entry exists.
3165
3166
3167Q0429: I would like to deliver mail addressed to a given domain to local
3168 mailboxes, but also to generate messages to the envelope senders.
3169
3170A0429: You can do this with an ``unseen'' router and an \%autoreply%\ transport,
3171 along the following lines:
3172
3173==> # Router
3174 auto_warning_r:
3175 driver = accept
3176 check_local_user
3177 domains = <domains you want to do this for>
3178 condition = ${if eq{$sender_address}{}{no}{yes}}
3179 transport = warning_t
3180 no_verify
3181 unseen
3182
3183 Place this router immediately before the normal \%localuser%\ router. The
3184 \unseen\ option means that the address is still passed on to the next
3185 router. The transport is configured like this:
3186
3187==> # Transport
3188 warning_t:
3189 driver = autoreply
3190 file = /usr/local/mail/warning.txt
3191 file_expand
3192 from = postmaster@your.domain
3193 to = $sender_address
3194 user = exim
3195 subject = Re: Your mail to $local_part@$domain
3196
3197 Note the use of the \condition\ option to avoid attempting to send a
3198 message when there is no sender (that is, when the incoming message is a
3199 bounce message). You can of course extend this to include other
3200 conditions. If you want to log the sending of messages, you can add
3201
3202==> log = /some/file
3203
3204 to the transport and also make use of the \once\ option if you want to
3205 send only one message to each sender.
3206
3207
3208Q0430: Whenever Exim tries to route a local address, it gives a permission
3209 denied error for the \(.forward)\ file, like this:
3210
3211==> 1998-08-10 16:55:32 0z5y2W-0000B8-00 == xxxx@yyy.zzz <xxxx@yyy.zz>
3212 D=userforward defer (-1): failed to open /home/xxxx/.forward
3213 (userforward router): Permission denied (euid=1234 egid=101)
3214
3215A0430: Have you remembered to make Exim setuid \/root/\?
3216
3217
3218Q0431: How do I configure Exim to allow arbitrary extensions in local parts, of
3219 the form \/+extension/\?
3220
3221A0431: Add this pre-condition to the relevant router:
3222
3223==> local_part_suffix = +*
3224
3225 If you want the extensions to be optional, also add the option
3226
3227==> local_part_suffix_optional
3228
3229 When the router runs, \$local_part$\ contains the local part with the
3230 extension removed, and the extension (if any) is in \$local_part_suffix$\.
3231 If you have set \check_local_user\, the test is carried out after the
3232 extension is removed.
3233
3234
3235Q0432: I use NIS for my user data. How can I stop Exim rejecting mail when my
3236 NIS servers are being restarted?
3237
3238A0432: Exim doesn't know that you are using NIS; it just calls the \^^getpwnam()^^\
3239 function, which is routed by nsswitch. Unfortunately, \^^getpwnam()^^\
3240 was never designed to be routed through NIS, and it returns NULL if the
3241 entry is not found or if the connection to the NIS server fails. This
3242 means that Exim cannot tell the difference between ``no such user'' and
3243 ``NIS is down''.
3244
3245 Crutches to help with this problem are \finduser_retries\ in Exim, and
3246 \^nscd^\ on the Unix side, but they are not perfect, and mail can still
3247 be lost. However, Nico Erfurth pointed out that you can create a router
3248 for Exim that tests for the availability of NIS, and force a defer if
3249 NIS is not running:
3250
3251==> check_nis:
3252 driver = redirect
3253 data = ${lookup {$local_part} nis {passwd}{}}
3254
3255 This should be placed before any router that makes any use of NIS,
3256 typically at the start of your local routers. How does it work? If
3257 your NIS server is reachable, the lookup will take place, and whether it
8e26e4bf 3258 succeeds or fails, the result is an empty string. This causes the
495ae4b0
PH
3259 router to decline, and the address is passed to the following routers.
3260 If your NIS server is down, the lookup defers, and this causes the
3261 router to defer. A verification of an incoming address gets a temporary
3262 rejection, and a delivery is deferred till later.
3263
3264
8e26e4bf
PH
3265Q0433: How can I arrange for a single address to be processed by both
3266 \%redirect%\ and \%accept%\?
495ae4b0
PH
3267
3268A0433: Check out the \unseen\ option.
3269
3270
3271Q0434: How can I redirect all local parts that are not in my system aliases to
3272 a single address? I tried using an asterisk in the system alias file
8e26e4bf 3273 with an \"lsearch*"\ lookup, but that sent all messages to the
495ae4b0
PH
3274 default address.
3275
3276A0434: If your alias file generates addresses in the local domain, they are
3277 also processed as a potential aliases. For example, suppose this is your
3278 alias file:
3279
3280==> caesar: jc
3281 anthony: ma
3282 *: brutus
3283
3284 The local part \/caesar/\ is aliased to \/jc/\, but that address is then
3285 reprocessed by the routers. As the address is in the local domain, the
3286 alias file is again consulted, and this time the default matches. In
3287 fact after the second aliasing, \/brutus/\ is also processed again from
3288 the start, and is aliased to itself. However, this happens only once,
3289 because the next time, Exim notices that the aliasing router has already
3290 processed \/brutus/\, so the router is skipped in order to avoid
3291 looping.
3292
3293 There are several ways of solving this problem; which one you use
3294 depends on your aliasing data.
3295
3296 (1) If the result of aliasing is always a local user name, that is,
3297 aliasing never generates another alias, you can use the
3298 \redirect_router\ option on the router to specify that processing
3299 the generated addresses must start at the next router. For example:
3300
3301==> redirect_router = userforward
3302
3303 assuming that the next router is called \%userforward%\. This
3304 ensures that there is at most one pass through the aliasing router.
3305
3306 (2) If you cannot rely on aliases generating non-aliases, it is often
3307 easier not to use a default alias, but instead to place a router
3308 such as the one below after all the other local routers (for the
3309 relevant domains):
3310
3311==> catch_unknown:
3312 driver = redirect
3313 domains = ...
3314 data = brutus@$domain
3315
3316 Note that the default aliasing technique works more successfully for
3317 virtual domains (see Q0401) because the generated address for the
3318 default is not usually in the same virtual domain as the incoming
3319 address.
3320
3321
3322Q0435: My alias file contains fully qualified addresses as keys, and some
3323 wildcard domains in the form @foo.bar. Can Exim handle these?
3324
3325A0435: You can handle fully qualified addresses with this router:
3326
3327==> qualified_aliases:
3328 driver = redirect
3329 data = ${lookup{$local_part@$domain}lsearch{/etc/aliases}}
3330
3331 (Add any other options you need for the \%redirect%\ router.) Place this
3332 router either before or after the default aliases router that looks up
3333 the local part only. (Or, if you have no unqualified aliases, replace
3334 the default router.)
3335
3336 To handle wildcards in the form @foo.bar you will need yet another
3337 router. (Wildcards of the form *@foo.bar can be handled by an lsearch*@
3338 lookup.) Something like this:
3339
3340==> wildcard_aliases:
3341 driver = redirect
3342 data = ${lookup{@$domain}lsearch{/etc/aliases}}
3343
3344 Place this after the routers that handle the more specific aliases.
3345
3346
3347
33485. FILTERING
3349
3350Q0501: My filter isn't working. How can I test it?
3351
3352A0501: Use the \-bf-\ option (\-bF-\ for a system filter) to test the basic operation
3353 of your filter. You can request debugging information for filtering only
3354 by adding \"-d-all+filter"\ to the command.
3355
3356
3357Q0502: What I really need is the ability to obtain the result of a pipe
3358 command so that I can filter externally and redirect internally. Is
3359 this possible?
3360
3361A0502: The result of a pipe command is not available to a filter, because Exim
3362 does not run any actual deliveries while filtering. It just sets up
3363 deliveries at this time. They all actually happen later. If you want to
3364 run pipes and examine their results, you need to set up a single
3365 delivery to a delivery agent such as \^procmail^\ which provides this kind
3366 of facility.
3367
3368 An possible alternative is to use the \"${run"\ expansion item to run an
3369 external command while filtering. In this case, you can make use of some
3370 of the results of the command.
3371
3372
3373Q0503: I received a message with a ::Subject:: line that contained a non-printing
3374 character (a carriage return). This messed up my filter file. Is there a
3375 way to get round it?
3376
3377A0503: Instead of \"$h_subject:"\ use \"${escape:$h_subject:}"\
3378
3379
3380Q0504: I want to search for \"$"\ in the subject line, but I can't seem to get
3381 the syntax.
3382
3383A0504: Try one of these:
3384
3385==> if $h_subject: contains \$ then ...
3386 if $h_subject: contains "\\$" then ...
3387
3388
3389Q0505: My problem is that Exim replaces \$local_part$\ with an empty string in the
3390 system filtering. What's wrong or what did I miss?
3391
3392A0505: A message may have many recipients. The system filter is run just once
3393 at the start of a delivery attempt. Consequently, it does not make sense
3394 to set \$local_part$\. Which recipient should it be set to? However, you
3395 can access all the recipients from a system filter via the variable
3396 called \$recipients$\.
3397
3398
3399Q0506: Using \$recipients$\ in a system filter gives me another problem: how can
3400 I do a string lookup if \$recipients$\ is a list of addresses?
3401
3402A0506: Check out the section of the filter specification called \*Testing a list of
3403 addresses*\. If that doesn't help, you may have to resort to calling an
3404 embedded Perl interpreter - but that is expensive.
3405
3406
3407Q0507: What are the main differences between using an Exim filter and using
3408 \^procmail^\?
3409
3410A0507: Exim filters and \^procmail^\ provide different facilities. Exim filters run
3411 at routing time, before any deliveries are done. A filter is like a
3412 ``\(.forward)\ file with conditions''. One of the benefits is de-duplication.
3413 Another is that if you forward, you are forwarding the original message.
3414
3415 However, this does mean that pipes etc. are not run at filtering time,
3416 nor can you change the headers, because the message may have other
3417 recipients and Exim keeps only a single set of headers.
3418
3419 \^procmail^\ runs at delivery time. This is for one recipient only, and so
3420 it can change headers, run pipes and check the results, etc. However, if
3421 it wants to forward, it has to create a new message containing a copy
3422 of the original message.
3423
3424 It's your choice as to which of these you use. You can of course use
3425 both.
3426
3427
3428Q0508: How can I allow the use of relative paths in users' filter files when
3429 the directories concerned are not available from the password data?
3430
3431A0508: You need to be running Exim 4.11 or later. You can then specify a value
3432 for \$home$\ by setting the router_home_directory option on the
3433 \%redirect%\ router.
3434
3435 For earlier releases, there is no way to specify the value of \$home$\
3436 for a \%redirect%\ router; it either comes from the password data as a
3437 result of \check_local_user\, or is unset.
3438
3439
3440Q0509: How can I set up a filter file to detect and block virus attachments?
3441
3442A0509: Exim's filter facilities aren't powerful enough to do much more than
3443 very crude testing. Most people that want virus checking are nowadays
3444 using one of the separate scanning programs such as \^exiscan^\ (see
3445 \?http://duncanthrax.net/exiscan/?\). There is some further information
3446 about scanning with Exim via \?http://www.timj.co.uk/linux/exim.php?\.
3447
3448
3449Q0510: Is it possible to write code for scanning messages in Python?
3450
3451A0510: \^elspy^\ is a layer of glue code that enables you to write Python code
3452 to scan email messages at SMTP time. \^elspy^\ also includes a small
3453 Python library with common mail-scanning tools, including an interface
3454 to SpamAssassin and a simple but effective virus detector. You can
4c04137d 3455 obtain \^elspy^\ from \?http://elspy.sourceforge.net/?\.
495ae4b0
PH
3456
3457
3458Q0511: Whenever my system filter uses a \mail\ command to send a message, I get
3459 the error \*User 0 set for address_reply transport is on the never_users
3460 list*\. What does this mean?
3461
3462A0511: The system filter runs as \/root/\ in Exim 4, unless you set
3463 \system_filter_user\ to specify otherwise. When you set up a delivery
3464 direct from a system filter (an autoreply is a special kind of
3465 ``delivery'') the transport runs as the same user, unless it has a
3466 \user\ setting of its own. Normally, deliveries are not allowed to run
3467 as \/root/\ as a security precaution; this is implemented by the
8e26e4bf 3468 \never_users\ option (see Q0039).
495ae4b0
PH
3469
3470 The easiest solution is to add this to your configuration:
3471
3472==> system_filter_user = exim
3473
3474 The system filter then runs as \/exim/\ instead of \/root/\.
3475 Alternatively, you can arrange for autoreplies from the system filter to
3476 use a special transport of their own, and set the \user\ option on that
3477 transport.
3478
3479
3480Q0512: I'm trying to reference the ::Envelope-To:: header in my filter, but
3481 \$h_envelope-to:$\ is always empty.
3482
3483A0512: ::Envelope-To:: is added at delivery time, by the transport. Therefore,
3484 the header doesn't exist at filter time. In a user filter, the values
3485 you probably want are in \$original_local_part$\ and
3486 \$original_domain$\. In a system filter, the complete list of all
3487 envelope recipients is in \$recipients$\.
3488
3489
3490Q0513: I want my system filter to freeze all mails greater than 500K in size,
3491 but to exclude those to a specific domain. However, I don't seem to be
3492 able to use \$domain$\ in a system filter.
3493
3494A0513: You cannot do this in a system filter, because a single message may have
3495 multiple recipients, some in the special domain, and some not. That is
3496 also the reason why \$domain$\ is not set in a system filter.
3497
3498 If you want to take actions on a per-recipient basis, you have to do it
3499 in a router. However, freezing is not appropriate, because freezing
3500 stops all deliveries. You could, however, delay delivery to all but the
3501 special domains by using something like this:
3502
3503==> delay_if_too_big:
3504 driver = redirect
3505 domains = !the.special.domain
3506 condition = ${if >{$message_size}{500K}{yes}{no}}
3507 allow_defer
3508 data = :defer: message too big.
3509
3510 However, there isn't an easy way of ``releasing'' such messages at
3511 present.
3512
3513
3514Q0514: When I try to send to two addresses I get an error in the filter
3515 file \*malformed address: , e@fgh.com may not follow a@bcd.com*\. What
3516 is going on?
3517
3518A0514: Have you got
3519
3520==> deliver "a@bcd.com, e@fgh.com"
3521
3522 in your filter? If so, that is your problem. You should have
3523
3524==> deliver a@bcd.com
3525 deliver e@fgh.com
3526
3527 Each \deliver\ command expects just one address.
3528
3529
3530
35316. DELIVERY
3532
3533Q0601: What does the error \*Neither the xxx router nor the yyy transport set
3534 a uid for local delivery of...*\ mean?
3535
3536A0601: Whenever Exim does a local delivery, it runs a process under a specific
3537 user and group id (uid and gid). For deliveries into mailboxes, and to
3538 pipes and files set up by forwarding, it normally picks up the uid/gid
3539 of the receiving user. However, if an address is directed to a pipe or a
3540 file by some other means, such an entry in the system alias file of the
3541 form
3542
3543==> majordomo: |/local/mail/majordomo ...
3544
3545 then Exim has to be told what uid/gid to use for the delivery. This can
4c04137d 3546 be done either on the router that handles the address, or on the
495ae4b0
PH
3547 transport that actually does the delivery. If a pipe is going to run a
3548 setuid program, then it doesn't matter what uid Exim starts it out with,
3549 and so the most straightforward thing is to put
3550
3551==> user = exim
3552
3553 on either the router or the transport. A setting on the transport
3554 overrides a setting on the router, so if the same transport is being
3555 used with several routers, you should set the user on it only if you
3556 want the same uid to be used in all cases.
3557
3558 In the default configuration, the transports used for file and pipe
3559 deliveries are the ones called \address_file\ and \address_pipe\. You
3560 can specify different transports by setting, for example,
3561
3562==> pipe_transport = special_pipe_transport
3563
3564 on the \%system_aliases%\ router. Then you can set up \%special_pipe_transport%\
3565
3566==> special_pipe_transport:
3567 driver = pipe
3568 user = ????
3569
3570 which will be used only for pipe deliveries from that one router.
3571 What you put for the ???? is up to you, and depends on the particular
3572 circumstances.
3573
3574
3575Q0602: Exim keeps crashing with segmentation errors (signal 11 or 139) during
3576 delivery. This seems to happen when it is about to contact a remote
3577 host or when a delivery is deferred.
3578
3579A0602: This could be a problem with Exim's databases. Try running a delivery
3580 with debugging turned on. If the last line of the debug output is
3581 something like this:
3582
3583==> locked /var/spool/exim/db/retry.lockfile
3584
3585 the crash is happening inside the DBM library. Check that your DBM
3586 library is correctly installed. In particular, if you have installed a
3587 second DBM library onto a system that already had one, check that its
3588 version of \(ndbm.h)\ is being seen first. For example, if the new
3589 version is in \(/usr/local/include)\, check that there isn't another
3590 version in \(/usr/include)\. If you are using Berkeley db, you can set
3591
3592==> USE_DB=yes
3593
3594 in your \(Local/Makefile)\ to avoid using \(ndbm.h)\ altogether. This is
3595 particularly relevant for version 2 (or later) of Berkeley db, because
3596 no \(ndbm.h)\ file is distributed with it. Another thing you can try is
3597 to run
3598
3599==> exim_dumpdb /var/spool/exim retry
3600
3601 to see if it also crashes, or build the \^test_dbfn^\ tool and fiddle
3602 around with it. If both fail, it is most almost certainly a problem with
3603 your DBM library. You could try to update it, or force Exim to use
3604 another library. See the file \(doc/dbm.discuss.txt)\ for hints about
3605 this.
3606
3607
3608Q0603: How can mails that are being routed through routers that do not set
3609 \check_local_user\ be delivered under the uid of the recipient?
3610
3611A0603: Q0601 contains background information on this. If you are using, say, an
3612 alias file to direct messages to specific mailboxes, you can use
3613 the \user\ option on either the router or the transport to set the uid.
3614 What you put in the setting depends on how the required uid is to be
3615 found. It could be looked up in a file or computed somehow from the
3616 local part, for example.
3617
3618
3619Q0604: I want to use MMDF-style mailboxes. How can I get Exim to append the
4c04137d 3620 ctrl-A characters that separate individual emails?
495ae4b0
PH
3621
3622A0604: Set the \message_suffix\ option in the \%appendfile%\ transport. In fact,
3623 for MMDF mailboxes you need a prefix as well as a suffix to get it
3624 working right, so your transport should contain these settings:
3625
3626==> message_prefix = "\1\1\1\1\n"
3627 message_suffix = "\1\1\1\1\n"
3628
3629 Also, you need to change the \check_string\ and \escape_string\ settings so
3630 that the escaping happens for lines in the message that happen to begin
3631 with the MMDF prefix or suffix string, rather than ``From'' (the default):
3632
3633==> check_string = "\1\1\1\1\n"
3634 escape_string = "\1\1\1\1 \n"
3635
3636 Adding a space to the line is sufficient to prevent it being taken as a
3637 separator.
3638
3639
3640Q0605: If a user's mailbox is over quota, is there a way for me to set it up so
3641 that the mail bounces to the sender and is not stored in the mail queue?
3642
3643A0605: In the retry section of the configuration, put
3644
3645==> *@your.dom.ain quota
3646
3647 That is, provide no retry timings for over quota errors. They will then
3648 bounce immediately. Alternatively, you can set up retries for a short
3649 time only, or use something like this:
3650
3651==> *@your.dom.ain quota_7d
3652 *@your.dom.ain quota F,2h,15m; F,3d,1h
3653
3654 which bounces immediately if the user's mailbox hasn't been read for 7
3655 days, but otherwise tries for up to 3 days after the first quota
3656 failure.
3657
3658
3659Q0606: I'm using tmail to do local deliveries, but when I turned on the
3660 \use_crlf\ option on the \%pipe%\ transport (tmail prefers \"@\r@\n"\
3661 terminations) message bodies started to vanish.
3662
4c04137d 3663A0606: You need to unset the \message_prefix\ option, or change it so that its
495ae4b0
PH
3664 default \"@\n"\ terminator becomes \"@\r@\n"\. For example, the
3665 transport could be:
3666
3667==> local_delivery_mbx:
f0884f39
PH
3668 driver = pipe
3669 command = /usr/local/bin/tmail $local_part
3670 user = exim
3671 current_directory = /
495ae4b0
PH
3672 use_crlf
3673 message_prefix =
3674
3675 The reason for this is as follows: tmail uses the line terminator on
3676 the first line it sees to determine whether lines are terminated by
3677 \"@\r@\n"\ or \"@\n"\. If the latter, it moans to stderr and changes subsequent
3678 \"@\n"\ terminators to \"@\r@\n"\. The default setting of the \message_prefix\
3679 option is \"From ...@\n"\, and this is unaffected by the \use_crlf\ option.
3680 If you don't change this, tmail sees the first line terminated by
3681 \"@\n"\ and prepends \"@\r"\ to the \"@\n"\ terminator on all subsequent
3682 lines. However, if \use_crlf\ is set, Exim makes all other lines
3683 \"@\r@\n"\ terminated, leading to doubled \"@\r@\r@\n"\ lines and
3684 corrupt mbx mailboxes.
3685
3686
3687Q0607: When I activate ``return receipt'' for example in Netscape Mailbox
3688 sending options, then I get an error message from Exim... something
3689 like \*not supported*\. Can I activate delivery confirmations?
3690
3691A0607: Exim does not support any kind of delivery notification.
3692
3693 (1) You can configure it to recognize headers such as
3694 \Return-receipt-to:\ if you wish.
3695
3696 (2) Some people want MSN (message status notification). Such services
3697 are implemented in MUAs, and don't impact on the MTA at all.
3698
3699 (3) I investigated the RFCs which describe the DSN (delivery status
3700 notification) system. However, I was unable to specify any sensible way
3701 of actually doing anything with the data. There were comments on the
3702 mailing list at the time; many people, including me, conclude that DSN
3703 is in practice unworkable. The killer problem is with forwarding and
3704 aliasing. Do you propagate the DSN data with the generated addresses?
3705 Do you send back a ``reached end of the DSN world'' or ``expanded'' message?
3706 Do you do this differently for different kinds of aliasing/forwarding?
3707 For a user who has a \(.forward)\ file with a single address in, this
3708 might seem easy - just propagate the data. But what if there are several
3709 forwardings? If you propagate the DSN data, the sender may get back
3710 several DSN messages - and should the sender really know about the
3711 detail of the receiver's forwarding arrangements? There isn't really
3712 any way to distinguish between a \(.forward)\ file that is forwarding
3713 and one that is a mini mailing list. And so on, and so on. There are so
3714 many questions that don't have obvious answers.
3715
3716
3717Q0608: What does the message \*retry time not reached [for any host]*\ on the log
3718 mean? Why won't Exim try to deliver the message?
3719
3720A0608: That is not an error. It means exactly what it says. A previous attempt
3721 to deliver to that address failed with a temporary error, and Exim
3722 computed the earliest time at which to try again. This can apply to
3723 local as well as to remote deliveries. For remote deliveries, each host
3724 (if there are several) has its own retry time.
3725
3726 If you are running on a dial-up host, the rest of this answer probably
3727 does not apply to you. Go and read Q1404 instead. If your host is
3728 permanently online, read on...
3729
3730 Some MTAs have a retrying schedule for each message. Exim does not work
3731 like this. Retry timing is normally host-based for remote deliveries and
3732 address-based for local deliveries. (There are some exceptions for certain
3733 kinds of remote failure - see \*Errors in outgoing SMTP*\ in the manual.)
3734
3735 If a new message arrives for a failing address and the retry time has
3736 not yet arrived, Exim will log \*retry time not reached*\ and leave the
3737 message on the queue, without attempting delivery. Similarly, if a queue
3738 runner notices the message before the time to retry has arrived, it
3739 writes the same log entry. When the retry time has past, Exim attempts
3740 delivery at the next queue run. If you want to know when that will be,
3741 run the exinext utility on the address, for example:
3742
3743==> exinext user@some.domain
3744
3745 You can suppress these messages on the log by including \"-retry_defer"\
3746 in the setting of \log_selector\. You can force a delivery attempt on a
3747 specific message (overriding the retry time) by means of the -M option:
3748
3749==> exim -M 10hCET-0000Bf-00
3750
3751 If you want to do this for the entire queue, use the \-qf-\ option.
3752
3753
3754Q0609: Exim seems to be sending the same message twice, according to the log,
3755 although there is a difference in capitalization of the local part of
3756 the address.
3757
3758A0609: That is correct. The RFCs are explicit in stating that capitalization
3759 matters for local parts. For remote domains, Exim is not entitled to
3760 assume case independence of local parts. I know, it is utterly silly,
3761 and it causes a lot of grief, but that's what the rules say. Here is a
3762 quote from RFC 2821:
3763
3764 ... a command verb, an argument value other than a mailbox local-part,
3765 and free form text MAY be encoded in upper case, lower case, or any
3766 mixture of upper and lower case with no impact on its meaning. This
3767 is NOT true of a mailbox local-part. The local-part of a mailbox
3768 MUST BE treated as case sensitive. Therefore, SMTP implementations
3769 MUST take care to preserve the case of mailbox local-parts. Mailbox
3770 domains are not case sensitive. In particular, for some hosts the
3771 user "smith" is different from the user "Smith". However, exploiting
3772 the case sensitivity of mailbox local-parts impedes interoperability
3773 and is discouraged.
3774
3775
3776Q0610: How can I force the next retry time for a host to be now?
3777
3778A0610: You can change the retry time with the \^exim_fixdb^\ utility, but its
3779 interface is very clumsy. If you have a message for the host on the
3780 queue, the simplest thing to do is to force a delivery with the \-M-\
3781 command line option. If delivery succeeds, the retry data will get
3782 cleared. If the host is past the cutoff time, so that messages are
3783 bouncing immediately without trying a delivery, you can use \-odq-\ to
3784 put a message on the queue without a delivery attempt, and then use
3785 \-M-\ on it.
3786
3787
3788Q0611: I set up \"|/bin/grep Subject|/usr/bin/smbclient -M <netbiosname>"\ as an
3789 alias but it doesn't work.
3790
3791A0611: That is a shell command line. Exim does not run pipe commands under a
3792 shell by default (for added security - and it saves a process). You
3793 need something like
3794
3795==> "|/bin/sh -c '/bin/grep Subject|/usr/bin/smbclient -M <netbiosname>'"
3796
3797
3798Q0612: Why does the \%pipe%\ transport add a line starting with \">From"\ to
3799 messages?
3800
3801A0612: Actually, it adds a line starting with \"From"\ followed by a space.
3802 This is commonly referred to as the \"From_"\ line, to emphasize the
3803 fact that \"From"\ is followed by a space and not a colon. This is a
3804 pseudo-header line that contains the envelope sender address and the
3805 time of delivery. It originated as a separator line in Berkeley format
3806 mailboxes, but is also used in other contexts. (And yes, it is often
3807 confused with the ::From:: header line, and this causes a lot of grief.
3808 The use of \"From_"\ was one of the really bad email design decisions.)
3809
3810 Exim's \%pipe%\ transport adds this pseudo-header line by default
3811 because \(/usr/ucb/vacation)\ needs it, and that is one of the the most
3812 common uses of piping. The \^procmail^\ local delivery agent also makes
3813 use of the \"From_"\ line. If you do not want it, change the setting of
3814 \message_prefix\ on the \%pipe%\ transport. For example, to remove the
3815 line altogether, use
3816
3817==> message_prefix =
3818
3819 If you are not piping to \(/usr/ucb/vacation)\ or \^procmail^\, it is
3820 likely that you do not need a \"From_"\ line, and indeed it may cause
3821 problems if it is present.
3822
3823 One user reported that this line gave trouble when a pipe was used to
3824 send messages to Courier's \^deliverquota^\ program. The line was
3825 retained with the message, and caused problems for MS Exchange 2000 when
3826 retrieving messages with its built-in POP collector. Specifically, it
3827 caused Exchange to not be able to recognise message attachments.
3828
3829
3830Q0613: I have set \fallback_hosts\ on my \%smtp%\ transport, but after the error
3831 \*sem@chat.ru cannot be resolved at this time*\ Exim isn't using them.
3832
3833A0613: \fallback_hosts\ works only if an attempt at delivery to the original
3834 host(s) fails. In this case, Exim couldn't even resolve the domain
3835 \(chat.ru)\ to discover what the original hosts were, so it never got as far
3836 as the transport. However, see Q0315 for a possible solution.
3837
3838
3839Q0614: After the holidays my ISP has always hundreds of e-mails waiting for me.
3840 These are forced down Exim's throat in one go. Exim spawns a lot of
3841 kids, but is there some limit to the number of processes it creates?
3842
3843A0614: Unless you have changed \smtp_accept_queue_per_connection\ it should
3844 spawn only that many processes per connection (default 10). Your ISP
3845 may be making many connections, of course. That is limited by
3846 \smtp_accept_max\.
3847
3848
3849Q0615: When a message in the queue got to 12h old, Exim wrote \*retry timeout
3850 exceeded*\ and removed all messages in the queue to this host - even
3851 recent messages. How I can avoid this behaviour? I only want to remove
3852 messages that have exceeded the maximum retry time.
3853
3854A0615: Exim's retrying is host-based rather than message-based. The philosophy
3855 is that if a host has been down for a very long time, there is no point
3856 in keeping messages hanging around. However, you might like to check
3857 out \delay_after_cutoff\ in the \%smtp%\ transport. It doesn't do what you
3858 want, but it might help.
3859
3860
3861Q0616: Can Exim add a ::Content-Length:: header to messages it delivers?
3862
3863A0616: You could include something like
3864
3865==> headers_remove = "content-length"
3866 headers_add = "Content-Length: $message_body_size"
3867
3868 to the \%appendfile%\ transport. However, the use of ::Content-Length:: can
3869 cause several problems, and is not recommended unless you really know
3870 what you are doing. There is a discussion of the problems in
3871 \?http://home.netscape.com/eng/mozilla/2.0/relnotes/demo/content-length.html?\.
3872
3873
3874Q0617: Exim seems to be trying to deliver a message every 10 minutes, though
3875 the retry rules specify longer times after a while, because it is
3876 writing a log entry every time, like this:
3877
3878==> 1999-08-26 14:51:19 11IVsE-000MuP-00 == example@example.com T=smtp defer
3879 (-34): some host address lookups failed and retry time not reached for
3880 other hosts or connection limit reached
3881
3882A0617: It is looking at the message every 10 minutes, but it isn't actually
3883 trying to deliver. It's looking up \(example.com)\ in the DNS and finding
3884 this information:
3885
3886==> example.com. MX 10 example-com.isp.example.com.
3887 example.com. MX 0 mail.example.com.
3888 mail.example.com. A 202.77.183.45
3889 A lookup for example-com.isp.example.com. yielded NXDOMAIN
3890
3891 The last line means that there is no address (A) record in the DNS for
3892 \(example-com.isp.example.com)\. That accounts for \*some host address
3893 lookups failed*\, but the retry time for \(mail.example.com)\ hasn't been
3894 reached, which accounts for \*retry time not reached for other hosts*\.
3895
3896
3897Q0618: I am trying to set exim up to have a automatic failover if it sees that
3898 the system that it is sending all mail to is down.