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39THE EXIM FAQ
40------------
41
42This is the FAQ for the Exim Mail Transfer Agent. Many thanks to the many
43people who provided the original information. This file would be amazingly
44cluttered if I tried to list them all. Suggestions for corrections,
45improvements, and additions are always welcome.
46
8e26e4bf 47This version of the FAQ applies to Exim 4.43 and later releases.
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48
49References of the form Cnnn, Fnnn, Lnnn, and Snnn are to the sample
50configuration, filter, \^^local_scan()^^\, and ``useful script'' files. These
51are hyperlinked from the HTML version of this FAQ. They can also be found in
52the separately distributed directory called \(config.samples)\. The primary
53location is
54
55\?ftp://ftp.csx.cam.ac.uk/pub/software/email/exim/exim4/config.samples.tar.gz?\
56\?ftp://ftp.csx.cam.ac.uk/pub/software/email/exim/exim4/config.samples.tar.bz2?\
57
58There are brief descriptions of these files at the end of this document.
59
60Philip Hazel
8e26e4bf 61Last update: 14-October-2004
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62
63
64The FAQ is divided into the following sections:
65
66 0. General Debugging
67 1. Building and Installing
68 2. Routing in general
69 3. Routing to remote hosts
70 4. Routing for local delivery
71 5. Filtering
72 6. Delivery
73 7. Policy controls
74 8. Rewriting addresses
75 9. Headers
76 10. Performance
77 11. Majordomo
78 12. Fetchmail
79 13. Perl
80 14. Dial-up and ISDN
81 15. UUCP
82 16. Modifying message bodies
83 17. Encryption (TLS/SSL)
84 20. Millennium
85 50. Miscellaneous
86 91. Mac OS X
87 92. FreeBSD
88 93. HP-UX
89 94. BSDI
90 95. IRIX
91 96. Linux
5e0b134b 92 97. Sun systems
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93 98. Configuration cookbook
94 99. List of sample configurations
95
96
97
980. GENERAL DEBUGGING
99
100Q0001: Exim is crashing. What is wrong?
101
102A0001: Exim should never crash. The author is always keen to know about
103 crashes, so that they can be diagnosed and fixed. However, before you
104 start sending me email, please check that you are running the latest
105 release of Exim, in case the problem has already been fixed. The
106 techniques described below can also be useful in trying to pin down
107 exactly which circumstances caused the crash and what Exim was trying to
8e26e4bf 108 do at the time. If the crash is reproducible (by a particular message,
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109 say) keep a copy of that message.
110
111
112Q0002: Exim is not working. What is wrong? How can I check what it is doing?
113
114A0002: Exactly how is it not working? Check the more specific questions in the
115 other sections of this FAQ. Some general techniques for debugging are:
116
117 (1) Look for information in Exim's log files. These are in the \(log)\
118 directory in Exim's spool directory, unless you have configured a
119 different path for them. Serious operational problems are reported
120 in paniclog.
121
122 (2) If the problem involves the delivery of one or more messages, try
123 forcing a delivery with the \-M-\ option and also set the \-d-\
124 option, to cause Exim to output debugging information. For example:
125
126==> exim -d -M 0z6CXU-0005RR-00
127
128 The output is written to the standard error stream. You need to have
129 admin privileges to use \-M-\ and \-d-\.
130
131 (3) If the problem involves incoming SMTP mail, try using the \-bh-\
132 option to simulate an incoming connection from a specific host,
133 for example:
134
135==> exim -bh 10.9.8.7
136
137 This goes through the motions of an SMTP session, without actually
138 accepting a message. Information about various policy checks is
139 output. You will need to know how to pretend to be an SMTP client.
140
141 (4) If the problem involves lack of recognition or incorrect handling
142 of local addresses, try using the \-bt-\ option with debugging turned
143 on, to see how Exim is handling the address. For example,
144
145==> exim -d -bt z6abc
146
147 shows you how it would handle the local part \"z6abc"\.
148
149
150Q0003: What does the error \*Child process of address_pipe transport returned
8e26e4bf 151 127 from command xxx*\ mean?
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152
153A0003: It means that when a transport called \%address_pipe%\ was run to pass an
154 email message by means of a pipe to another process running the command
8e26e4bf 155 xxx, the return code from that command was 127, which indicates some kind
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156 of error (the success return code is 0).
157
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158 The most common meaning of exit code 127 is that when Exim tried to run
159 the command \(xxx)\, it failed. One cause of this might be incorrect
160 permissions on the file containing the command. See also Q0026.
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161
162
163Q0004: My virtual domain setup isn't working. How can I debug it?
164
165A0004: You can use an exim command with \-d-\ to get it to show you how it is
166 processing addresses. You don't actually need to send a message; use the
167 \-bt-\ option like this:
168
169==> exim -d -bt localpart@virtualhost
170
171 This will show you which routers it is using. If the problem appears
172 to be with the expansion of an option setting, you can use the
173 \debug_print\ option on a router to get Exim to output the expanded
174 string values as it goes along.
175
176
177Q0005: Why is Exim not rejecting incoming messages addressed to non-existent
178 users at SMTP time?
179
180A0005: This is controlled by the ACL that is run for each incoming RCPT
181 command. It is defined by the \acl_smtp_rcpt\ option. You can check this
182 part of your configuration by using the \-bh-\ option to run a simulated
183 SMTP session, during which Exim will tell you what things it is
184 checking.
185
186
187Q0006: I've put an entry for \"*.my.domain"\ in a DBM lookup file, but it isn't
188 getting recognized.
189
190A0006: You need to request ``partial matching'' by setting the search type to
191 \partial-dbm\ in order for this to work.
192
193
194Q0007: I've put the entry \"*@domain.com"\ in a lookup database, but it isn't
195 working. The expansion I'm using is:
196
197==> ${lookup{${lc:$sender_address}}dbm{/the/file} ...
198
199A0007: As no sender address will ever be //*@domain.com// this will indeed have
200 no effect as it stands. You need to tell Exim that you want it to look
201 for defaults after the normal lookup has failed. In this case, change the
202 search type from \"dbm"\ to \"dbm*@"\. See the section on \*Default values in
203 single-key lookups*\ in the chapter entitled \*File and database
204 lookups*\ in the Exim manual.
205
206
207Q0008: If I run \"./exim -d -bt user@domain"\ all seems well, but when I send
208 a message from my User Agent, it does not arrive at its destination.
209
210A0008: Try sending a message directly to Exim by typing this:
211
212==> exim -v user@domain
213 <some message, could be empty>
214 .
215
216 If the message gets delivered to a remote host, but never arrives at its
217 final destination, then the problem is at the remote host. If, however,
218 the message gets through correctly, then the problem may be between your
219 User Agent and Exim. Try setting Exim's \log_selector\ option to include
220 \"+arguments"\, to see with which arguments the UA is calling Exim.
221
222
223Q0009: What does \*no immediate delivery: too many messages received in one SMTP
224 connection*\ mean?
225
226A0009: An SMTP client may send any number of messages down a single SMTP
227 connection to a server. Initially, an Exim server starts up a delivery
228 process as soon as a message is received. However, in order not to start
229 up too many processes when lots of messages are arriving (typically
230 after a period of downtime), it stops doing immediate delivery after a
231 certain number of messages have arrived down the same connection. The
232 threshold is set by \smtp_accept_queue_per_connection\, and the default
233 value is 10. On large systems, the value should be increased. If you are
234 running a dial-in host and expecting to get all your mail down a single
235 SMTP connection, then you can disable the limit altogether by setting
236 the value to zero.
237
238
239Q0010: Exim puts \*for \[address]\*\ in the ::Received:: headers of some, but not all,
240 messages. Is this a bug?
241
242A0010: No. It is deliberate. Exim inserts a ``for'' phrase only if the incoming
243 message has precisely one recipient. If there is more than one
244 recipient, nothing is inserted. The reason for this is that not all
245 recipients appear in the ::To:: or ::Cc:: headers, and it is considered a
246 breach of privacy to expose such recipients to the others. A common
247 case is when a message has come from a mailing list.
248
249
250Q0011: Instead of \^exim_dbmbuild^\, I'm using a homegrown program to build DBM
251 (or cdb) files, but Exim doesn't seem to be able to use them.
252
253A0011: Exim expects there to be a binary zero value on the end of each key used
254 in a DBM file if you use the \"dbm"\ lookup type, but not for the \"dbmnz"\
255 lookup type or for the keys of a cdb file. Check that you haven't
256 slipped up in this regard.
257
258
259Q0012: Exim is unable to route to any remote domains. It doesn't seen to be
260 able to access the DNS.
261
262A0012: Try running \"exim -d+resolver -bt \[remote address]\"\. The \-d-\
263 options turns on debugging output, and the addition of \"+resolver"\
264 will make it show the resolver queries it is building and the results of
265 its DNS queries. If it appears unable to contact any name servers, check
266 the contents and permissions of \(/etc/resolv.conf)\.
267
268
269Q0013: What does the error message \*transport system_aliases: cannot find
270 transport driver "redirect" in line 92*\ mean?
271
272A0013: \%redirect%\ is a router, not a transport. You have put a configuration
273 for a router into the transports section of the configuration file.
274
275
276Q0014: Exim is timing out after receiving and responding to the DATA command
277 from one particular host, and yet the client host also claims to be
278 timing out. This seems to affect only certain messages.
279
280A0014: This kind of problem can have many different causes.
281
282 (1) This problem has been seen with a network that was dropping all
283 packets over a certain size, which mean that the first part of the SMTP
284 transaction worked, but when the body of a large message started
285 flowing, the main data bits never got through the network. See also
286 Q0017.
287
288 (2) This can also happen if a host has a broken TCP stack and won't
289 reassemble fragmented datagrams.
290
291 (3) A very few ISDN lines have been seen which failed when certain data
292 patterns were sent through them, and replacing the routers at both end
293 of the link did not fix things. One of them was triggered by more than 4
294 X's in a row in the data.
295
296
297Q0015: What does the message \*Socket bind() to port 25 for address (any)
298 failed: address already in use*\ mean?
299
300A0015: You are trying to run an Exim daemon when there is one already running -
301 or maybe some other MTA is running, or perhaps you have an SMTP line in
302 \(/etc/inetd.conf)\ which is causing \(inetd)\ to listen on port 25.
303
304
305Q0016: I've set \"verify = header_syntax"\ in my ACL, but this causes Exim to
306 complain about header lines like \"To: Work: Jim <jims@email>,
307 Home: Bob <bobs@email>"\ which look all right to me. Is this a bug?
308
309A0016: No. Header lines such as ::From::, ::To::, etc., which contain addresses, are
310 structured, and have to be in a specific format which is defined in RFC
311 2822. Unquoted colons are not allowed in the ``phrase'' part of an email
312 address (they are OK in other headers such as ::Subject::). The correct
313 form for that header is
314
315==> To: "Work: Jim" <jims@email>, "Home: Bob" <bobs@email>
316
317 You will sometimes see unquoted colons in ::To:: and ::Cc:: headers, but only
318 in connection with name lists (called ``groups''), for example:
319
320==> To: My friends: X <x@y.x>, Y <y@w.z>;,
321 My enemies: A <a@b.c>, B <b@c.d>;
322
323 Each list must be terminated by a semicolon, as shown.
324
325
326Q0017: Whenever Exim tries to deliver a specific message to a particular
327 server, it fails, giving the error \*Remote end closed connection after
328 data*\ or \*Broken pipe*\ or a timeout. What's going on?
329
330A0017: \*Broken pipe*\ is the error you get on some OS when the remote host just
331 drops the connection. The alternative is \*connection reset by peer*\.
332 There are many potential causes. Here are some of them (see also Q0068):
333
334 (1) There are some firewalls that fall over on binary zero characters
335 in email. Have a look, e.g. with \"hexdump -c mymail | tail"\ to see if
336 your mail contains any binary zero characters.
337
338 (2) There are broken SMTP servers around that just drop the connection
339 after the data has been sent if they don't like the message for some
340 reason (e.g. it is too big) instead of sending a 5xx error code. Have
341 you tried sending a small message to the same address?
342
343 It has been reported that some releases of Novell servers running NIMS
344 are unable to handle lines longer than 1024 characters, and just close
345 the connection. This is an example of this behaviour.
346
347 (3) If the problem occurs right at the start of the mail, then it could
348 be a network problem with mishandling of large packets. Many emails are
349 small and thus appear to propagate correctly, but big emails will
350 generate big IP datagrams.
351
352 There have been problems when something in the middle of the network
353 mishandles large packets due to IP tunnelling. In a tunnelled link, your
354 IP datagrams gets wrapped in a larger datagram and sent over a network.
355 This is how virtual private networks (VPNs), and some ISP transit
356 circuits work. Since the datagrams going over the tunnel require a
357 larger packet size, the tunnel needs a bigger maximum transfer unit
358 (MTU) in the network handling the tunnelled packets. However, MTUs
359 are often fixed, so the tunnel will try to fragment the packets.
360
361 If the systems outside the tunnel are using path MTU discovery, (most
362 Sun Sparc Solaris machines do by default), and set the DF (don't
363 fragment) bit because they don't send packets larger than their \(local)\
364 MTU, then ICMP control messages will be sent by the routers at the
365 ends of the tunnel to tell them to reduce their MTU, since the tunnel
366 can't fragment the data, and has to throw it away. If this mechanism
367 stops working, e.g. a firewall blocks ICMP, then your host never
368 knows it has hit the maximum path MTU, but it has received no ACK on
369 the packet either, so it continues to resend the same packet and the
370 connection stalls, eventually timing out.
371
372 You can test the link using pings of large packets and see what works:
373
f0884f39 374==> ping -s host 2048
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375
376 Try reducing the MTU on the sending host:
377
f0884f39 378==> ifconfig le0 mtu 1300
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379
380 Alternatively, you can reduce the size of the buffer Exim uses for SMTP
381 output by putting something like
382
383==> DELIVER_OUT_BUFFER_SIZE=512
384
385 in your \(Local/Makefile)\ and rebuilding Exim (the default is 8192).
386 While this should not in principle have any effect on the size of
387 packets sent, in practice it does seem to have an effect on some OS.
388
389 You can also try disabling path MTU discovery on the sending host. On
390 Linux, try:
391
392==> echo 1 >/proc/sys/net/ipv4/ip_no_pmtu_disc
393
394 For a general discussion and information about other operating systems, see
395 \?http://www.netheaven.com/pmtu.html?\. If disabling path MTU discovery
396 fixes the problem, try to find the broken or misconfigured
397 router/firewall that swallows the ICMP-unreachable packets. Increasing
398 timeouts on the receiving host will not work around the problem.
399
400
401Q0018: Why do messages not get delivered down the same connection when I do
402 something like: \"exim -v -R @aol.com"\? For other domains, I do this and
403 I see the appropriate \*waiting for passed connections to get used*\
404 messages.
405
406A0018: Recall that Exim does not keep separate queues for each domain, but
407 operates in a distributed fashion. Messages get into its `waiting for
408 host x' hints database only when a delivery has been tried, and has had
409 a temporary error. Here are some possibilities:
410
411 (1) The messages to \(aol.com)\ got put in your queue, but no previous
412 delivery attempt occured before you did the \-R-\. This might have been
413 because of your settings of \queue_only_load\, \smtp_accept_queue\, or any
414 other option that caused no immediate delivery attempt on arrival. If
415 this is the case, you can try using \-qqR-\ instead of \-R-\.
416
417 (2) You have set \connection_max_messages\ on the smtp transport, and
418 that limit was reached. This would show as a sequence of messages
419 down one connection, then another sequence down a new connection, etc.
420
421 (3) Exim tried to pass on the SMTP connection to another message, but
422 that message was in the process of being delivered to \(aol.com)\ by some
423 other process (typically, a normal queue runner). This will break the
424 sequence, though the other delivery should pass its connection on to
425 other messages if there are any.
426
427 (4) The folk at \(aol.com)\ changed the MX records so the host names have
428 changed - or a new host has been added. I don't know how likely this is.
429
430 (5) Exim is not performing as it should in this regard, for some reason.
431 Next time you have mail queued up for \(aol.com)\, try running
432
433==> exim_dumpdb /var/spool/exim wait-remote_smtp
434
435 to see if those messages are listed among those waiting for the relevant
436 \(aol.com)\ hosts.
437
438
439Q0019: There seems to be a problem in the string expansion code: it doesn't
440 recognize references to headers such as \"${h_to}"\.
441
442A0019: The only valid syntax for header references is (for example) \"$h_to:"\
443 because header names are permitted by RFC 2822 to contain a very wide
444 range of characters. A colon (or white space) is required as the
445 terminator.
446
447
448Q0020: Why do connections to my machine's SMTP port take a long time to respond
449 with the banner, when connections to other ports respond instantly? The
450 delay is sometimes as long as 30 seconds.
451
452A0020: These kinds of delay are usually caused by some kind of network problem
453 that affects outgoing calls made by Exim at the start of an incoming
454 connection. Configuration options that cause outgoing calls are:
455
456 (1) \rfc1413_hosts\ and \rfc1413_query_timeout\ (for \*ident*\ calls).
457 Firewalls sometimes block ident connections so that they time out,
458 instead of refusing them immediately. This can cause this problem.
459 See Q5023 for a discussion of the usefulness of \*ident*\.
460
461 (2) The \host_lookup\ option, the \host_reject_connection\ option, or a
462 condition in the ACL that runs at connection time requires the
463 remote host's name to be looked up from its IP address. Sometimes
464 these DNS lookups time out. You can get this effect with ACL
465 statements like this:
466
467==> deny hosts = *.x.example
468
469 If at all possible, you should use IP addresses instead of host
9c2b45c9 470 names in blocking lists in order to avoid this problem.
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471
472 You can use the \-bh-\ option to get more information about what is
473 happening at the start of a connection. However, note that the \-bh-\
474 option does not provide a complete simulation. In particular, no
475 \*ident*\ checks are done, so it won't show up a delay problem that is
476 related to (1) above.
477
478
479Q0021: What does \*failed to create child process to send failure message*\ mean?
480 This is a busy mail server with \smtp_accept_max\ set to 500, but this
481 problem started to occur at about 300 incoming connections.
482
483A0021: Some message delivery failed, and when Exim wanted to send a bounce
484 message, it was unable to create a process in which to do so. Probably
485 the limit on the maximum number of simultaneously active processes has
486 been reached. Most OS have some means of increasing this limit, and in
487 some operating systems there is also a limit per uid which can be
488 varied.
489
490
491Q0022: What does \*No transport set by system filter*\ in a log line mean?
492
493A0022: Your system filter contains a \"pipe"\ or \"save"\ or \"mail"\ command,
494 but you have not set the corresponding option which specifies which
495 transport is to be used. You need to set whichever of
496 \system_filter_pipe_transport\, \system_filter_file_transport\ or
497 \system_filter_reply_transport\ is relevant.
498
499
500Q0023: Why is Exim refusing to relay, saying \*failed to find host name from IP
501 address*\ when I have the sender's IP address in an ACL condition? My
502 configuration contains this ACL statement:
503
504==> accept hosts = lsearch;/etc/mail/relaydomains:192.168.96.0/24
505
506A0023: When checking a host list, the items are tested in left-to-right
507 order. The first item in your list is a lookup on the incoming host's
508 name, so Exim has to determine the name from the incoming IP address in
509 order to perform the test. If it can't find the host name, it can't do
510 the check, so it gives up. You would have discovered what was going
511 on if you had run a test such as
512
513==> exim -bh 192.168.96.131
514
515 The solution is to put all explicit IP addresses first in the list.
516 Alternatively, you can split the ACL statement into two like this:
517
518==> accept hosts = lsearch;/etc/mail/relaydomains
519 accept hosts = 192.168.96.0/24
520
521 If the host lookup fails, the first \"accept"\ fails, but then the
522 second one is considered.
523
524
525Q0024: When I run \"exim -bd -q10m"\ I get \*PANIC LOG: exec of exim -q failed*\.
526
527A0024: This probably means that Exim doesn't know its own path so it can't
528 re-exec itself to do the first queue run. Check the output of
529
530==> exim -bP exim_path
531
532
533Q0025: I can't seem to get a pipe command to run when I include a \"${if"\
534 expansion in it. This fails:
535
536==> command = perl -T /usr/local/rt/bin/rtmux.pl \
537 rt-mailgate helpdesk \
538 ${if eq {$local_part}{rt} {correspond}{action}}
539
540A0025: You need some internal quoting in there. Exim expands each individual
541 argument separately. Because you have (necessarily) got spaces in your
542 \"${if"\ item, you have to quote that argument. Try
543
544==> command = perl -T /usr/local/rt/bin/rtmux.pl \
545 rt-mailgate helpdesk \
546 "${if eq {$local_part}{rt} {correspond}{action}}"
547
548 \**Warning:**\ If command starts with an item that requires quoting,
549 you cannot just put it in quotes, because a leading quote means that the
550 entire option setting is being quoted. What you have to do is to quote
551 the entire value, and use internally escaped quotes for the ones you
552 really want. For example:
553
554==> command = "\"${if ....}\" arg1 arg2"
555
556 Any backslashes in the expansion items will have to be doubled to stop
557 them being interpreted by the string reader.
558
559
560Q0026: I'm trying to get Exim to connect an alias to a pipe, but it always
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561 gives error code 127, with the comment \*(could mean unable to exec
562 or command does not exist)*\.
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563
564A0026: If your alias entry looks like this:
565
566==> alias: |"/some/command some parameters"
567
568 change it to look like this:
569
570==> alias: "|/some/command some parameters"
571
572
573Q0027: What does the error \*Spool file is locked*\ mean?
574
575A0027: This is not an error. All it means is that when an Exim delivery
576 process (probably started by a queue runner process) looked at a message
577 in order to start delivering it, it found that another Exim process was
578 already busy delivering it. On a busy system this is quite a common
579 occurrence. If you set \"-skip_delivery"\ in the \log_selector\ option,
580 these messages are omitted from the log.
581
582 The only time when this message might indicate a problem is if it is
583 repeated for the same message for a very long time. That would suggest
584 that the process that is delivering the message has somehow got stuck.
585
586
587Q0028: Exim is reporting IP addresses as 0.0.0.0 or 255.255.255.255 instead of
588 their correct values. What's going on?
589
590A0028: You are using a version of Exim built with gcc on an IRIX box.
591 See Q9502.
592
593
594Q0029: I can't seem to figure out why PAM support doesn't work correctly.
595
596A0029: There is a problem using PAM with shadow passwords when the calling
597 program is not running as \/root/\. Exim is normally running as the
8e26e4bf 598 Exim user when authenticating a remote host.
495ae4b0 599
8e26e4bf 600 (1) One solution can be found at \?http://www.e-admin.de/pam_exim/?\.
495ae4b0 601
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602 (2) PAM 0.72 allows authorization as non-\/root/\, using setuid helper
603 programs. Furthermore, in \(/etc/pam.d/exim)\ you can explicitly
604 specify that this authorization (using setuid helpers) is only
605 permitted for certain users and groups.
495ae4b0 606
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607 (3) Another approach is to authenticate using the \^saslauthd^\ daemon,
608 which has its own interface to PAM. The daemon runs as root, so
609 there is no access problem.
610
611 (4) One suggested solution was to set
612
613==> exim_group=shadow
614
615 in the configuration file, or the equivalent at build time. This is
616 very strongly discouraged. Do not do it! It works, but it's a
617 potential security exposure. Exim is intended to run as a
618 non-privileged user for much of the time. This setting gives it have
619 privileged access to crucial security information all of the time,
620 simply for the purposes of authentication (which Exim will only
621 spend a tiny part of its total time doing). The result is that a
622 successful compromise of the Exim system can give someone direct
623 access to the system passwords.
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624
625
626Q0030: I'm trying to use a query-style lookup for hosts that are allowed to
627 relay, but it is giving really weird errors.
628
629A0030: Does your query contain a colon character? Remember that host lists are
630 colon-separated, so you need to double any colons in the query. This
631 applies even if the query is defined as a macro.
632
633
634Q0031: Exim is rejecting connections from hosts that have more than one IP
635 address, for no apparent reason.
636
637A0031: You are using Solaris 7 or earlier, and have \"nis dns files"\ in
638 \(/etc/nsswitch.conf)\. Change this to \"dns nis files"\ to avoid hitting Sun
639 bug 1154236 (a bad interaction between NIS and the DNS).
640
641
642Q0032: Exim is failing to find the MySQL library, even though is it present
643 within \\LD_LIBRARY_PATH\\. I'm getting this error:
644
645==> /usr/local/bin/exim: fatal: libmysqlclient.so.6: open failed:
646 No such file or directory
647
648A0032: Exim is suid, and \\LD_LIBRARY_PATH\\ is ignored for suid binaries on a
649 Solaris (and other?) systems. What you should be doing is adding
650 \"-R/local/lib/mysql"\ to the same place in the compilation that you added
651 \"-L/local/lib/mysql"\. This tells the binary where to look without
652 needing a path variable.
653
654
655Q0033: What does the error \*lookup of host "xx.xx.xx" failed in yyy router*\
656 mean?
657
658A0033: You configured a \%manualroute%\ router to send the message to xx.xx.xx. When
659 it tried to look up the IP address for that host, the lookup failed
660 with a permanent error. As this is a manual routing, this is a
661 considered to be a serious error which the postmaster needs to know
662 about (maybe you have a typo in your file), and there is little point
663 in keeping on trying. So it freezes the message.
664
665 (1) Don't set up routes to non-existent hosts.
666
667 (2) If you must set up routes to non-existent hosts, and don't want
668 freezing, set the \host_find_failed\ option on the router to do something
669 other than freeze.
670
671
672Q0034: Exim works fine on one host, but when I copied the binary to another
673 identical host, it stopped working (it could not resolve DNS names).
674
675A0034: Is the new host running exactly the same operating system? Most
676 importantly, are the versions of the dynamically loaded libraries
677 (files with names like \(libsocket.so.1)\) the same on both systems? If not,
678 that is probably the cause of the problem. Either arrange for the
679 libraries to be the same, or rebuild Exim from source on the new host.
680
681
682Q0035: I set a \"hosts"\ condition in an ACL to do a lookup in a file of IP
683 addresses, but it doesn't work.
684
685A0035: Did you remember to put \"net-"\ at the start of the the search type? If
686 you set something like this:
687
688==> accept hosts = lsearch;/some/file
689
690 Exim searches the file for the host name, not the IP address. You need
691 to set
692
693==> accept hosts = net-lsearch;/some/file
694
695 to make it use the IP address as the key to the lookup.
696
697
698Q0036: Why do I get the error \*Permission denied: creating lock file hitching
699 post*\ when Exim tries to do a local delivery?
700
701A0036: Your configuration specifies that local mailboxes are all held in
702 single directory, via configuration lines like these (taken from the
703 default configuration):
704
705==> local_delivery:
706 driver = appendfile
707 file = /var/mail/$local_part
708
709 and the permissions on the directory probably look like this:
710
711==> drwxrwxr-x 3 root mail 512 Jul 9 13:48 /var/mail/
712
713 Using the default configuration, Exim runs as the local user when doing
714 a local delivery, and it uses a lock file to prevent any other process
715 from updating the mailbox while it is writing to it. With those
716 permissions the delivery process, running as the user, is unable to
717 create a lock file in the \(/var/mail(\ directory. There are two solutions
718 to this problem:
719
720 (1) Set the \"write"\ and \"sticky bit"\ permissions on the directory, so
721 that it looks like this:
722
723==> drwxrwxrwt 3 root mail 512 Jul 9 13:48 /var/mail/
724
725 The \"w"\ allows any user to create new files in the directory, but
726 the \"t"\ bit means that only the creator of a file is able to remove
727 it. This is the same setting as is normally used with the \(/tmp)\
728 directory.
729
730 (2) Arrange to run the local_delivery transport under a specific group
731 by changing the configuration to read
732
733==> local_delivery:
734 driver = appendfile
735 file = /var/mail/${local_part}
736 group = mail
737
738 The delivery process still runs under the user's uid, but with the
739 group set to \"mail"\. The group permission on the directory allows
740 the process to create and remove the lock file.
741
742 The choice between (1) and (2) is up to the administrator. If the
743 second solution is used, users can empty their mailboxes by updating
744 them, but cannot delete them.
745
f0884f39 746 If your problem involves mail to \/root/\, see also Q0039.
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747
748
749Q0037: I am experiencing mailbox locking problems with Sun's \"mailtool"\ used
750 over a network.
751
752A0037: See Q9705 in the Sun-specific section below.
753
754
755Q0038: What does the error message \*error in forward file (filtering not
756 enabled): missing or malformed local part*\ mean?
757
758A0038: If you are trying to use an Exim filter, you have forgotten to enable
759 the facility, which is disabled by default. In the \%redirect%\ router
760 (in the Exim run time configuration file) you need to set
761
762==> allow_filter = true
763
764 to allow a \(.forward)\ file to be used as an Exim filter. If you are not
765 trying to use an Exim filter, then you have put a malformed address in
766 the \(.forward)\ file.
767
768
769Q0039: I have installed Exim, but now I can't mail to \/root/\ any more. Why is
770 this?
771
772A0039: Most people set up \/root/\ as an alias for the manager of the host. If
773 you haven't done this, Exim will attempt to deliver to \/root/\ as if it
774 were a normal user. This isn't really a good idea because the delivery
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775 process would run as \/root/\. Exim has two trigger guards that stop
776 deliveries running as root. In the build-time configuration, there is a
777 setting called FIXED_NEVER_USERS, which defaults to \"root"\. This
778 setting cannot be overridden. In addition, the default runtime
779 configuration contains the option
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780
781==> never_users = root
782
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783 just to be on the safe side. If you really want to run local deliveries
784 as \/root/\, you must use a version of Exim that was built without the
785 FIXED_NEVER_USERS option, and remove the above line from the runtime
786 configuration, but it would be better to create an alias for \/root/\
787 instead.
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788
789
790Q0040: How can I stop undeliverable bounce messages (e.g. to routeable, but
791 undeliverable, spammer senders) from clogging up the queue for days?
792
793A0040: If at all possible, you should try to avoid getting into this situation
794 in the first place, for example, by verifying recipients so that you
795 do not accept undeliverable messages that lead to these bounces.
796 You can, however, configure Exim to discard failing bounce messages
797 early. Just set \ignore_bounce_errors_after\ to specify a (short) time
798 to keep them for.
799
800
801Q0041: What does the message \*unable to set gid=ddd or uid=ddd (euid=ddd):
802 local delivery to ... transport=ttt*\ mean?
803
804A0041: Have you remembered to make Exim setuid \/root/\? It needs root privilege if
805 it is to do any local deliveries, because it does them ``as the user''.
806 Note also that the partition from which Exim is running (where the
807 binary is installed) must not have the \nosuid\ mount option set. You
808 can check this by looking at its \(/etc/fstab)\ entry (or \(/etc/vfstab)\,
809 depending on your OS).
810
811
812Q0042: My ISP's mail server is rejecting bounce messages from Exim, complaining
813 that they have no sender. The SMTP trace does indeed show that the
814 sender address is \"<>"\. Why is the Sender on the bounce message empty?
815
816A0042: Because the RFCs say it must be. Your ISP is at fault. Send them this
817 extract from RFC 2821 section 6.1 (\*Reliable Delivery and Replies by
818 Email*\):
819
820 If there is a delivery failure after acceptance of a message, the
821 receiver-SMTP MUST formulate and mail a notification message. This
822 notification MUST be sent using a null (\"<>"\) reverse path in the
823 envelope. The recipient of this notification MUST be the address
824 from the envelope return path (or the ::Return-Path:: header line).
825 However, if this address is null (\"<>"\), the receiver-SMTP MUST NOT
826 send a notification.
827
828 The reason that bounce messages have no sender is so that they
829 themselves cannot provoke further bounces, as this could lead to a
830 unending exchange of undeliverable messages.
831
832
833Q0043: What does the error \*Unable to get interface configuration: 22 Invalid
834 argument*\ mean?
835
836A0043: This is an error that occurs when Exim is trying to find out the all the
837 IP addresses on all of the local host's interfaces. If you have lots of
838 virtual interfaces, this can occur if there are more than around 250 of
839 them. The solution is to set the option \local_interfaces\ to list just
840 those IP addresses that you want to use for making and receiving SMTP
841 connections.
842
843
844Q0044: What does the error \*Failed to create spool file*\ mean?
845
846A0044: Exim has been unable to create a file in its spool area in which to
847 store an incoming message. This is most likely to be either a
848 permissions problem in the file hierarchy, or a problem with the uid
849 under which Exim is running, though it could be something more drastic
850 such as your disk being full.
851
852 If you are running Exim with an alternate configuration file using a
853 command such as \"exim -C altconfig..."\, remember that the use of -C
cc5fdbc2 854 takes away Exim's root privilege, unless \\TRUSTED_CONFIG_LIST\\
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855 is set in \(Local/Makefile)\ and the corresponding file contains a
856 prefix which matches the alternative configuration file being used.
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857
858 Check that you have defined the spool directory correctly by running
859
860==> exim -bP spool_directory
861
862 and examining the output. Check the mode of this directory. It should
863 look like this, assuming you are running Exim as user \/exim/\:
864
865==> drwxr-x--- 6 exim exim 512 Jul 16 12:29 /var/spool/exim
866
867 If there are any subdirectories already in existence, they should have
868 the same permissions, owner, and group. Check also that you haven't got
869 incorrect permissions on superior directories (for example, \(/var/spool)\).
870 Check that you have set up the Exim binary to be setuid \/root/\. It should
871 look like this:
872
873==> -rwsr-xr-x 1 root xxx 502780 Jul 16 14:16 exim
874
875 Note that it is not just the owner that must be \/root/\, but also the third
876 permission must be \"s"\ rather than \"x"\.
877
878
879Q0045: I see entries in the log that mention two different IP addresses for the
880 same connection. Why is this? For example:
881
882==> H=tip-mp8-ncs-13.stanford.edu ([36.173.0.189]) [36.173.0.156]
883
884A0045: The actual IP address from which the call came is the final one.
885 Whenever there's something in parentheses in a host name, it is what the
886 host quoted as the domain part of an SMTP HELO or EHLO command. So in
887 this case, the client, despite being 36.173.0.156, issued the command
888
889==> EHLO [36.173.0.189]
890
891 when it sent your server the message. This is, of course, very
892 misleading.
893
894
895Q0046: A short time after I start Exim I see a defunct zombie process. What
896 is causing this?
897
898A0046: Your system must be lightly loaded as far as mail is concerned. The
899 daemon sets off a queue runner process when it is started, but it only
900 tidies up completed child processes when it wakes up for some other
901 reason. When there's nothing much going on, you occasionally see
902 defunct processes like this waiting to be dealt with. This is
903 perfectly normal.
904
905
906Q0047: On a reboot, or a restart of the mail system, I see the message \*Mailer
907 daemons: exim abandoned: unknown, malformed, or incomplete option
908 -bz sendmail*\. What does this mean?
909
910A0047: \-bz-\ is a Sendmail option requesting it to create a `configuration freeze
911 file'. Exim has no such concept and so does not support the option. You
912 probably have a line like
913
914==> /usr/lib/sendmail -bz
915
916 in some start-up script (e.g. \(/etc/init.d/mail)\) immedately before
917
918==> /usr/lib/sendmail -bd -q15m
919
920 The first of these lines should be commented out.
921
922
923Q0048: Whenever exim restarts it takes up to 3-5 minutes to start responding on
924 the SMTP port. Why is this?
925
926A0048: Something else is hanging onto port 25 and not releasing it. One place
927 to look is \(/etc/inetd.conf)\ in case for any reason an SMTP stream is
928 configured there.
929
930
931Q0049: What does the log message \*no immediate delivery: more than 10 messages
932 received in one connection*\ mean?
933
934A0049: A remote MTA sent a number of messages in a single SMTP session. Exim
935 limits the number of immediate delivery processes it creates as a
936 result of a single SMTP connection, in order to avoid creating a zillion
937 processes on systems that can have many incoming connections. If you are
938 dialing in to collect mail from your ISP, you should probably set
939 \smtp_accept_queue_per_connection\ to some number larger than 10, or
940 arrange to start a queue runner for local delivery (using \-ql-\)
941 immediately after collecting the mail.
942
943
944Q0050: I am getting complaints from a customer who uses my Exim server for
945 relaying that they are being blocked with a \*Too many connections*\
946 error.
947
948A0050: See \smtp_accept_max\, \smep_accept_max_per_host\ and \smtp_accept_reserve\.
949
950
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951Q0051: When I test my system filter with \-bf-\, I get the error \*filtering
952 command "fail" is disabled*\. Why is this?
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953
954A0051: Use the \-bF-\ option to test system filters. This gives you access to the
955 freeze and fail actions.
956
957
958Q0052: What does \*ridiculously long message header*\ in an error report mean?
959
960A0052: There has to be some limit to the length of a message's header lines,
961 because otherwise a malefactor could open an SMTP channel to your host,
962 start a message, and then just send characters continuously until your
8e26e4bf 963 host runs out of memory. (Exim stores all the header lines in main
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964 memory while processing a message). For this reason a limit is imposed
965 on the total amount of memory that can be used for header lines. The
966 default is 1MB, but this can be changed by setting \\HEADER_MAXSIZE\\ in
967 \(Local/Makefile)\ before building Exim. Exceeding the limit provokes
968 the ``ridiculous'' error message.
969
970
971Q0053: Exim on my host responds to a connection with \"220 *****..."\ and
972 won't understand \\EHLO\\ commands.
973
974A0053: This is the sign of a Cisco Pix ``Mailguard'' sitting in front of your
975 MTA. Pix breaks ESMTP and only does SMTP. It is a nuisance when you have
976 a secure MTA running on your box. Something like ``no fixup protocol
977 smtp 25'' in the Pix configuration is needed. It may be possible to do
978 this by logging into the Pix (using \^telnet^\ or \^ssh^\) and typing
979 \"no fixup smtp"\ to its console. (You may need to use other commands
980 before or after to set up configuration mode and to activate a changed
981 configuration. Consult your Pix documentation or expert.) See also
982 Q0078.
983
984
985Q0054: I'm getting an Exim configuration error \*unknown rewrite flag
986 character (m) in line 386*\ but I haven't used any flags on my rewriting
987 rules.
988
989A0054: You have probably forgotten to quote a replacement string that contains
990 white space.
991
992
993Q0055: What does the error \*Failed to open wait-remote_smtp database: Invalid
994 argument*\ mean?
995
996A0055: This is something that happens if you have existing DBM hints files when
997 you install a new version of Exim that is compiled to use a different or
998 upgraded DBM library. The simplest thing to try is
999
1000==> rm /var/spool/exim/db/*
1001
1002 This removes all the hints files. Exim will start afresh and build new
1003 ones. If the symptom recurs, it suggests there is some problem with your
1004 DBM library.
1005
1006
1007Q0056: We are using Exim to send mail from our web server. However, whenever a
1008 user sends an email it gets sent with the return path (envelope sender)
1009 //apache@server_name.com// because the PHP script is running as
1010 \/apache/\.
1011
1012A0056: You need to include \/apache/\ in the \trusted_users\ configuration option.
1013 Only trusted users are permitted to specify senders when mail is passed
1014 to Exim via the command line.
1015
1016
1017Q0057: We've got people complaining about attachments that don't show up
1018 as attachments, but are included in the body of the message.
1019
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1020A0057: In the past, these symptoms could be seen when some software passed a
1021 CRLF line terminated message via the command line, because Exim expected
1022 lines to be terminated by LF only, and so it preserved the CRs as data.
1023 Modern versions of Exim (4.21 or later) use heuristics to try to do the
1024 right thing with line endings.
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1025
1026
1027Q0058: What does the error \*failed to open DB file \(/var/spool/exim/db/retry)\:
1028 File exists*\ mean?
1029
1030A0058: This error is most often caused when a hints file that was written with
1031 one version of the Berkeley DB library is read by another version.
1032 Sometimes this can happen if you change from a binary version of Exim to
1033 a locally compiled version. Or it can happen if you compile and install
1034 a new version of Exim after changing Berkeley DB versions. You can find
1035 out which version your Exim is using by running:
1036
1037==> ldd /usr/sbin/exim
1038
1039 The solution to the problem is to delete all the files in the
1040 \(/var/spool/exim/db)\ directory, and let Exim recreate them.
1041
1042
1043Q0059: When my Outlook Express 6.0 client sends a STARTTLS command to begin a
1044 TLS session, Exim doesn't seem to receive it. The Outlook log shows
1045 this:
1046
1047==> SMTP: 14:19:27 [tx] STARTTLS
1048 SMTP: 14:19:27 [rx] 500 Unsupported command.
1049
1050 but the Exim debugging output shows this:
1051
1052==> SMTP<< EHLO xxxx
1053 SMTP>> 250-yyyy Hello xxxx [nnn.nnn.nnn.nnn]
1054 250-SIZE 52428800
1055 250-PIPELINING
1056 250-AUTH CRAM-MD5 PLAIN LOGIN
1057 250-STARTTLS
1058 250 HELP
1059 SMTP<< QUIT
1060
1061A0059: Turn off scanning of outgoing email in Norton Antivirus. If you aren't
1062 running Norton Antivirus, see if you are running some other kind of SMTP
1063 proxying, either on the client or on a firewall between the client and
1064 server. ``Unsupported command'' is not an Exim message.
1065
1066
1067Q0060: Why am I getting the error \*failed to expand \"/data/lists/lists/${lc"\
1068 for require_files: \"${lc"\ is not a known operator*\ for this setting:
1069
1070==> require_files = MAILMAN_HOME/lists/${lc:$local_part}/config.db
1071
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1072A0060: The value of \"require_files"\ is a list in which each item is
1073 separately expanded. In other words, the splitting into items happens
1074 before the string expansion. You need either to double the colon, or
1075 switch to a different list separator.
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1076
1077
1078Q0061: What does the error \*Too many ``Received'' headers - suspected mail
1079 loop*\ mean?
1080
1081A0061: Whenever a message passes through an MTA, a ::Received:: header gets
1082 added. Exim counts the number of these headers in incoming messages. If
1083 there are more than the value of \received_headers_max\ (default 30),
1084 Exim assumes there is some kind of mail routing loop occurring. For
1085 example, host A passes the message to host B, which immediately passes
1086 it back to host A. Check the ::Received:: headers and the mail logs to
1087 determine exactly what is going on.
1088
1089 One common cause of this problem is users with accounts on both systems
1090 who set up each one to forward to the other, thinking that will cause
1091 copies of all messages to be delivered on both of them.
1092
1093
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1094Q0062: When I try to start an Exim daemon with \-bd-\ it crashes. I ran a
1095 debugger and discovered that the crash is happening in the function
1096 \^^getservbyname()^^\. What's going on?
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1097
1098A0062: What have you got in the file \(/etc/nsswitch.conf)\? If it contains this
1099 line:
1100
1101==> services: db files
1102
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1103 try removing the \"db"\. Your system is trying to look in some kind of
1104 database before searching the file \(/etc/services)\, and there is an
1105 incompatibility the is causing the function \^^getservbyname()^^\ crash.
1106 This is an OS problem. See, for instance:
1107
1108 \?http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=129025?\
1109
1110 Another workaround in Exim is to set
1111
1112==> daemon_smtp_port = 25
1113
1114 in the configuration, to stop Exim calling \^^getservbyname()^^\.
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1115
1116
1117Q0063: When I try to start an Exim daemon, nothing happens. There is no
1118 process, and nothing is written to the Exim log.
1119
1120A0063: Check to see if anything is written to \(syslog)\. This problem can be
1121 caused by a permission problem that stops Exim from writing to its log
1122 files, especially if you've specified that they should be written
1123 somewhere other than under Exim's spool directory. You could also try
1124 running the daemon with debugging turned on.
1125
1126
1127Q0064: When I run \"exim -d test@domain"\ it delivers fine, but when I send a
1128 message from the \^mail^\ command, I get \*User unknown*\ and the mail
1129 is saved in \(dead.letter)\.
1130
1131A0064: It looks as if Exim isn't being called by \^mail^\; instead it is
1132 calling some other program (probably Sendmail). Try running the command
1133
1134==> /usr/sbin/sendmail -bV
1135
1136 (If you get \*No such file or directory*\ or \*Command not found*\ you
1137 are running Solaris or IRIX. Try again with \(/usr/lib/sendmail)\.) The
1138 output should be something like this:
1139
1140==> Exim version 4.05 #1 built 13-Jun-2002 10:27:15
1141 Copyright (c) University of Cambridge 2002
1142
1143 If you don't see this, your Exim installation isn't fully operational.
1144 If you are running FreeBSD, see Q9201. For other systems, see Q0114.
1145
1146
1147Q0065: When (as \/root/\) I use -C to run Exim with an alternate configuration
1148 file, it gives an error about being unable to create a spool file when
1149 trying to run an \%autoreply%\ transport. Why is this?
1150
1151A0065: When Exim is called with -C, it passes on -C to any instances of itself
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1152 that it calls (so that the whole sequence uses the same config file).
1153 However, Exim gives up its root privilege if any user except \/root\/
1154 passes a -C option to use a non-default configuration file, and that
1155 includes the case where Exim re-execs itself to regain root privilege.
1156 Thus it can't write to the spool.
1157
cc5fdbc2 1158 The fix for this is to use the \\TRUSTED_CONFIG_LIST\\ build-time
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1159 option. This defines a file containing a list of 'trusted' prefixes for
1160 configuration files. Any configuration file specified with -C, if it
1161 matches a prefix listed in that file, will be used without dropping root
1162 privileges (as long as it is not writeable by a non-root user).
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1163
1164
1165Q0066: What does the message \*unable to set gid=xxx or uid=xxx*\ mean?
1166
1167A0066: This message is given when an Exim process is unable to change uid or
1168 gid when it needs to, because it does not have root privilege. This is a
1169 serious problem that prevents Exim from carrying on with what it is
1170 doing. The two most common situations where Exim needs to change uid/gid
1171 are doing local deliveries and processing users' filter files. There are
1172 two common causes of this error:
1173
1174 (1) You have forgotten to make the exim binary setuid to \/root/\. This
1175 means that it can never change uid/gid in any situation. Also, the
1176 setuid binary must reside on a disk partition that does not have the
1177 \"nosuid"\ mount option set.
1178
1179 (2) The exim binary is setuid, but you have configured Exim so that,
1180 while trying to verify an address at SMTP time, it runs a router
1181 that needs to change uid/gid. Because Exim runs as \/exim/\ and not
1182 \/root/\ while receiving messages, the router is unable to change
1183 uid and therefore it cannot operate. The usual example of this is a
1184 \%redirect%\ router for users' filter files.
1185
1186 Setting the \user\ or \check_local_user\ options on a \redirect\
1187 router causes this to happen (except in the special case when the
1188 redirection list is provided by the \data\ option and does not
1189 contain \":include:"\).
1190
1191 The solution is to set \no_verify\ on the router that is causing the
1192 problem. This means that it is skipped when an address is being
1193 verified. In ``normal'' configurations where the router is indeed
1194 handling users' filter files, this is quite acceptable, because you
1195 do not usually need to process a filter file in order to verify that
1196 the local part is valid. See, for example, the \%userforward%\
1197 router in the default configuration.
1198
1199
1200Q0067: What does the error \*too many unrecognized commands*\ mean?
1201
1202A0067: There have been instances of network abuse involving mail sent out by
1203 web servers. In most cases, unrecognizable commands are sent as part of
1204 the SMTP session. A real MTA never sends out such invalid commands. Exim
1205 allows a few unrecognized commands in a session to permit humans who are
1206 testing to make a few typos (it responds with a 5xx error). However, if
1207 Exim receives too many such commands, it assumes that it is dealing with
1208 an abuse of some kind, and so it drops the connection.
1209
1210
1211Q0068: Exim times out when trying to connect to some hosts, though those hosts
1212 are known to be up and running. What's the problem?
1213
1214A0068: There could be a number of reasons for this (see also Q0017). The
1215 obvious one is that there is a networking problem between the hosts.
1216 If you can ping between the hosts or connect in other ways, the problem
1217 might be caused by ECN (Explicit Congestion Notification) being enabled
1218 in your kernel. ECN uses TCP flags originally assigned to TOS - it's a
1219 "new" invention, and some hosts and routers are known to be confused if
1220 a client uses it. If you are running Linux, you can turn ECN off by
1221 running this command:
1222
1223==> /bin/echo "0" > /proc/sys/net/ipv4/tcp_ecn
1224
1225 This has also been reported to cure web connection problems from Mozilla
1226 and Netscape browsers in Linux when there were no problems with Windows
1227 Netscape browsers.
1228
1229
1230Q0069: What does the error \*SMTP data timeout (message abandoned) on connection
1231 from...*\ mean?
1232
1233A0069: It means that there was a timeout while Exim was reading the contents of
1234 a message on an incoming SMTP connection. That is, it had successfully
1235 accepted a MAIL command, one or more RCPT commands, and a DATA command,
1236 and was in the process of reading the data itself. The length of timeout
1237 is controlled by the \smtp_receive_timeout\ option.
1238
1239 If you get this error regularly, the cause may be incorrect handling of
1240 large packets by a router or firewall. The maximum size of a packet is
1241 restricted on some links; routers should split packets that are larger.
1242 There is a feature called ``path MTU discovery'' that enables a sender
1243 to discover the maximum packet size over an entire path (multiple
1244 Internet links). This can be broken by misconfigured firewalls and
1245 routers. There is a good explanation at \?http://www.netheaven.com/pmtu.html?\.
1246 Reducing the MTU on your local network can sometimes work round this
1247 problem. See Q0017 (3) for further discussion.
1248
1249
1250Q0070: What does the error \*SMTP command timeout on connection from...*\ mean?
1251
1252A0070: Exim was expecting to read an SMTP command from the client, but no
1253 command was read within the \smtp_receive_timeout\ time limit.
1254
1255
1256Q0071: What does the error \*failed to open DB file \(/var/spool/exim//db/retry)\:
1257 Illegal argument*\ mean?
1258
1259A0071: See Q0058. The cause of this error is usually the same.
1260
1261
1262Q0072: Exim will deliver to normal aliases, and aliases that are pipes or
1263 files, but it objects to aliases that involve \":include:"\ items,
1264 complaining that it can't change gid or uid. Why is this?
1265
1266A0072: See Q0066 for a general answer. The problem happens during verification
1267 of an incoming SMTP message, not during delivery itself. In this
1268 particular case, you must have set up your aliasing router with a \user\
1269 setting. This causes Exim to change uid/gid when reading \":include:"\
1270 files. If you do not need the detailed verification provided by the
1271 router, the easy solution is to set \no_verify\ so that the router isn't
1272 used during verification.
1273
1274 Otherwise, if you set \user\ on the router in order to provide a user
1275 for delivery to pipes or files, one solution is to put the \user\
1276 setting on the transports instead of on the router. You may need to
1277 create some special transports just for this router. The alternative is
1278 to supply two different routers, one with \user\ and \no_verify\, and
1279 the with \verify_only\ but no \user\ setting.
1280
1281
1282Q0073: I'm seeing log file corruption, with parts of log lines getting mangled
1283 by other log entries.
1284
1285A0073: The only time this has been seen is when several servers were writing to
1286 the same log files over NFS. Exim assumes that its log file is on local
1287 disk, and using NFS, especially for more than one server, will not work.
1288
1289
1290Q0074: What does the error message \*remote delivery process count got out of
1291 step*\ mean?
1292
1293A0074: Exim uses subprocesses for remote deliveries; this error means that the
1294 master process expected to have a child process running, but found there
1295 were none. Prior to release 4.11, this error could be caused by running
1296 Exim under \^strace^\ on a Linux system, because stracing causes
1297 children to be ``stolen'' such that a parent that tries to wait for
1298 ``any of my children'' is told that it has none. Current releases of
1299 Exim have code to get round this problem.
1300
1301
1302Q0075: I'm using LDAP, and some email addresses that contain special characters
1303 are causing parsing errors in my LDAP lookups.
1304
1305A0075: You should be using \"${quote_ldap:$local_part}"\ instead of just
1306 \"$local_part"\ in your lookups.
1307
1308
1309Q0076: I've configured Exim to use \^syslog^\ for its logs, with the main and
1310 reject logs sent to different files, but whenever a message is rejected,
1311 I get one message on the reject log and two messages on the main log.
1312
1313A0076: You are probably putting your reject items into the main log as well;
1314 remember \^syslog^\ levels are inclusive (for example, \"mail.info"\
1315 includes all higher levels, so a \"mail.notice"\ message will be caught
1316 by a \"mail.info"\ descriptor).
1317 Test this by running the command:
1318
f0884f39 1319==> logger -p mail.notice test
495ae4b0 1320
8e26e4bf
PH
1321 and seeing which logs it goes into. From Exim release 4.31 it is
1322 possible to disable the rejectlog by setting \write_rejectlog\ false.
495ae4b0
PH
1323
1324
1325Q0077: I've installed Exim and it is delivering mail just fine. However, when I
1326 try to read mail from my PC I get \*connection rejected*\ or \*unable to
1327 connect*\.
1328
1329A0077: See Q5021.
1330
1331
1332Q0078: Exim is logging the unknown SMTP command \"XXXX"\ from my client hosts,
1333 and they are unable to authenticate.
1334
1335A0078: This is a sign of a Cisco PIX firewall getting in the way. It does not
1336 support ESMTP, and turns EHLO commands into XXXX. You should configure
1337 the Pix to leave SMTP alone; see Q0053 for how to do this.
1338
1339
1340Q0079: Our new PIX firewall is causing problems with incoming mail. How can
1341 this be fixed?
1342
1343A0079: See Q0053 and Q0078. If some messages get through and others do not,
1344 see also Q0017.
1345
1346
1347Q0080: Am I to understand that the database lookups must only return one value?
1348 They can not return a list of values? The documentation seems to
1349 indicate that it's possible to return a list.
1350
1351A0080: Lookups can be used in two different situations, and what they return is
1352 different in the two cases. (Be thankful Exim 3 is gone; there was yet
1353 another case!)
1354
1355 (1) You can use a lookup in any expanded string. The syntax is
1356
1357==> ${lookup ..... }
1358
1359 In this case, whatever is looked up replaces the expansion item. It
1360 may be one value or a list of values. Whether a single value or a
1361 list is acceptable or not depends on where you are using the string
1362 expansion. If it is for an option that expects just one value, then
1363 only one value is allowed (for example).
1364
1365 (2) You can make use of the lookup mechanism to test whether something
1366 (typically a host name or IP address) is in a list. For example,
1367
1368==> hosts = a : b : c
1369
1370 in an ACL tests whether the calling host's name matches ``a'', or
1371 ``b'', or ``c''. Now, suppose you want to keep the list of names in
1372 a database, or cdb file, or NIS map, or... By writing
1373
1374==> hosts = pgsql;select ....
1375
1376 you are saying to Exim: ``Run this lookup; if it succeeds, behave as
1377 if the host is in the list; if it fails, the host is not in the
1378 list.'' You are using the indexing mechanism of the database as a
1379 fast way of checking a list. A simpler example is
1380
1381==> hosts = lsearch;/some/file
1382
1383 where the file contains the list of hosts to be searched.
1384
1385 The complication happens when a list is first expanded before being
1386 interpreted as a list. This happens in a lot of cases. You can therefore
1387 write either of these:
1388
1389==> hosts = cdb;/some/file
1390 hosts = ${lookup{something}cdb{/some/file}}
1391
1392 but they have different meanings. The first means ``see if the host name
1393 is in the list in this file''. The second means ``run this lookup and
1394 use the result of the lookup as a list of host items to check''. In the
1395 second case, the list could contain multiple values (colon separated),
1396 and one of those values could even be ``cdb;/some/file''.
1397
1398 Flexibility does lead to complexity, I'm afraid.
1399
1400
1401Q0081: What does \*error in redirect data: included file xxxx is too big*\
1402 mean?
1403
1404A0081: You are trying to include a very large file in a redirection list, using
1405 the \":include:"\ feature. Exim has a built-in limit on the size, as a
1406 safety precaution. The default is 1 megabyte. If you want to increase
1407 this, you have to rebuild Exim. In your \(Local/Makefile)\, put
1408
1409==> MAX_INCLUDE_SIZE = whatever
1410
1411 and then rebuild Exim. The value is a number of bytes, but you can give
1412 it as a parenthesized arithmetic expression such as \"(3*1024*1024)"\.
1413 However, an included file of more than a megabyte is likely to be quite
1414 inefficient. How many addresses does yours contain? You get the best
1415 performance out of Exim if you arrange to send mailing list messages
1416 with no more than about 100 recipients (in order to get parallelism in
1417 the routing).
1418
1419
1420Q0082: What does \*relocation error: /lib/libnss_dns.so.2: symbol
1421 __libc_res_nquery, version GLIBC_PRIVATE not defined in file
1422 libresolv.so.2 with link time reference*\ mean?
1423
1424A0082: You have updated \^glibc^\ while an Exim daemon is running. Stop and
1425 restart the daemon.
1426
1427
1428Q0083: Netscape on Unix is sending messages containing an unqualified user name
1429 in the ::Sender:: header line, which Exim is rejecting because I have
1430 set \"verify = header_syntax"\. How can I fix this?
1431
1432A0083: The only thing you can do in Exim is to set the
1433 \sender_unqualified_hosts\ option to allow unqualified sender addresses
1434 form the relevant hosts; of course, this applies to all sender
1435 addresses, not just the ::Sender:: header line.
1436
1437 Alternatively, you can configure Netscape not to include the header line
1438 in the first place. Add the following line to the
1439 \($HOME/.netscape/preferences.js)\ and \($HOME/.netscape/liprefs.js)\
1440 files:
1441
1442==> user_pref("mail.suppress_sender_header", true);
1443
8e26e4bf 1444 Netscape must be shut down while doing this.
495ae4b0
PH
1445
1446
1447Q0084: I want to set up an alias that pipes a message to \^gpg^\ and then pipes
1448 the result to \^mailx^\ to resubmit the message, but when I use my
1449 tested command in an alias file, I get an error from \^gpg^\.
1450
1451A0084: Probably you are using a shell command with two pipe symbols in it. An
1452 alias like this:
1453
1454==> gpg-xxx: "|gpg <options> | mailx <options"
1455
1456 does not work, because Exim does not run pipes under a shell by default.
1457 You must call a shell explicitly if you want to make use of the shell's
1458 features for double-piping, either by piping to \"/bin/sh"\ with a
1459 suitable \"-c"\ option, or by piping to a shell script.
1460
1461
1462Q0085: I see a lot of \*rejected EHLO ... syntactically invalid argument(s)*\.
1463 I know it's because of the underscore in the host name, but is there a
1464 switch to allow Exim to accept mail from such hosts?
1465
1466A0085: Yes. Add this to your configuration:
1467
1468==> helo_allow_chars = _
1469
1470 For more seriously malformed host names, see \helo_accept_junk_hosts\.
1471 See also Q0732.
1472
1473
1474Q0086: What does \*SMTP protocol violation: synchronization error (next input
1475 sent too soon)*\ mean?
1476
1477A0086: SMTP is a ``lock-step'' protocol, which means that, at certain points in
1478 the protocol, the client must wait for the server to respond before
1479 sending more data. Exim checks for correct behaviour, and issues this
1480 error if the client sends data too soon. This protects against
1481 malefactious clients who send a bunch of SMTP commands (usually to
1482 transmit spam) without waiting for any replies.
1483
8e26e4bf
PH
1484 This error is also provoked if a client unexpectedly tries to start up a
1485 TLS session immediately on connection, without using the STARTTLS
1486 command. See Q1707 for a discussion of this case.
495ae4b0
PH
1487
1488
1489Q0087: What does \*rejected after DATA: malformed address: xx@yy may not follow
8e26e4bf 1490 <xx@yy> : failing address in "from" header*\ mean?
495ae4b0
PH
1491
1492A0087: Your DATA ACL contains
1493
1494==> verify = header_syntax
1495
1496 and an incoming message contained the line
1497
1498==> From: xx@yy <xx@yy>
1499
1500 This is syntactically invalid. The contents of an address in a header
1501 line are either just the address, or a ``phrase'' followed by an address
1502 in angle brackets. In the latter case, the ``phrase'' must be quoted if
1503 it contains special characters such as @. The following are valid
1504 versions of the bad header:
1505
1506==> From: xx@yy
1507 From: "xx@yy" <xx@yy>
1508
1509 though why on earth anything generates this kind of redundant nonsense I
1510 can't think.
1511
1512
1513Q0088: The Windows mailer SENDFILE.EXE sometimes hangs while trying to send a
1514 message to Exim 4, and eventually times out. It worked flawlessly with
1515 Exim 3. What has changed?
1516
1517A0088: Exim 4 sets an obscure TCP/IP parameter called TCP_NODELAY. This
1518 disables the "Nagle algorithm" for the TCP/IP transmission. The Nagle
1519 algorithm can improve network performance in interactive situations such
1520 as a human typing at a keyboard, by buffering up outgoing data until the
1521 previous packet has been acknowledged, and thereby reducing the number
1522 of packets used. This is not relevant for mail transmission, which
1523 mostly consists of quite large blocks of data; setting TCP_NODELAY
1524 should improve performance. However, it seems that some Windows clients
1525 do not function correctly if the server turns off the Nagle algorithm.
1526 If you are using Exim 4.23 or later, you can set
1527
1528==> tcp_nodelay = false
1529
1530 This stops Exim setting TCP_NODELAY on the sockets created by the
1531 listening daemon.
1532
1533
1534Q0089: What does the error \*kernel: application bug: exim(12099) has SIGCHLD
1535 set to SIG_IGN but calls wait()*\ mean?
1536
8e26e4bf
PH
1537A0089: This was a bad interaction between a change to the Linux kernel and some
1538 ``belt and braces'' programming in Exim. The following explanation is
1539 taken from Exim's change log:
495ae4b0
PH
1540
1541 When Exim is receiving multiple messages on a single connection, and
1542 spinning off delivery processess, it sets the SIGCHLD signal handling to
1543 SIG_IGN, because it doesn't want to wait for these processes. However,
1544 because on some OS this didn't work, it also has a paranoid call to
1545 \^waitpid()^\ in the loop to reap any children that have finished. Some
1546 versions of Linux now complain (to the system log) about this
1547 ``illogical'' call to \^waitpid()^\. I have therefore put it inside a
1548 conditional compilation, and arranged for it to be omitted for Linux.
1549
1550 I am pretty sure I caught all the places in Exim where this happened.
1551 However, there are still occasional reports of this error. I have not
1552 heard of any resolutions, but my current belief is that they are caused
1553 by something that Exim calls falling foul of the same check. There was
1554 at one time a suspicion that the IPv6 stack was involved.
1555
1556
1557Q0090: I can't seem to get a pipe command to run when I include a \"${lookup"\
1558 expansion in it.
1559
1560A0090: See Q0025.
1561
1562
1563Q0091: Why is Exim giving the error \*Failed to send message from address_reply
1564 transport*\ when I run it using -C to specify an alternate
1565 configuration?
1566
1567A0091: See Q0065.
1568
1569
8e26e4bf 1570Q0092: The error message \*Program received signal SIGINT, Interrupt.*\ occurs
2683a02a 1571 when I try to use Exim with PostgreSQL.
8e26e4bf
PH
1572
1573A0092: Check that you have not set
2683a02a
PH
1574
1575==> log_statement=true
1576
8e26e4bf
PH
1577 in the PostgreSQL configuration file. It seems that this causes
1578 PostgreSQL to return logging information as the first row in a query
1579 result, which totally confuses Exim.
2683a02a
PH
1580
1581
495ae4b0
PH
1582
15831. BUILDING AND INSTALLING
1584
1585Q0101: I'm having a problem with an Exim RPM.
1586
1587A0101: Normally the thing to do if you have a problem with an RPM package is
1588 to contact the person who built the package first, not the person who
1589 made the software that's in the package. You can usually find out who
1590 made a package using the following command:
1591
1592==> rpm --query --package --queryformat '%{PACKAGER}\n' <rpm-package-file>
1593
1594 where \[rpm-package-file]\ is the actual file, e.g. \(exim-3.03-2.i386.rpm)\.
1595 Or, if the package is installed on your system:
1596
1597==> rpm --query --queryformat '%{PACKAGER}\n' <package-name>
1598
1599 where \[package-name]\ is the name component of the package, e.g. \"exim"\.
1600 If the packager is unable or unwilling to help, only then should you
1601 contact the actual author or associated mailing list of the software.
1602
1603 If you discover through the querying process that you can't tell who
1604 the person (or company or group) is who built the package, or that they
1605 no longer exist at the given address, then you should reconsider
1606 whether you want a package from an unknown source on your system.
1607
1608 If you discover through the querying process that you yourself are the
1609 person who built the package, then you should either (a) contact the
1610 author or associated mailing list, or (b) reconsider whether you ought
1611 to be building and distributing RPM packages of software you don't
1612 understand.
1613
1614 Similar rules of thumb govern other binary package formats, including
1615 debs, tarballs, and POSIX packages.
1616
1617
1618Q0102: I can't get Exim to compile with Berkeley DB version 2.x or 3.x.
1619
1620A0102: Have you set \"USE_DB=yes\" in \(Local/Makefile)\? This causes Exim to use the
1621 native interface to the DBM library instead of the compatibility
1622 interface, which needs a header called \(ndbm.h)\ that may not exist on your
1623 system.
1624
1625
1626Q0103: I'm getting an \*undefined symbol*\ error for \"hosts_ctl"\ when I try to
1627 build Exim. (On some systems this error is \*undefined reference to
1628 'hosts_ctl'*\.)
1629
1630A0103: You should either remove the definition of \\USE_TCP_WRAPPERS\\ or add
1631 \"-lwrap"\ to your \\EXTRALIBS\\ setting in Local/Makefile.
1632
1633
1634Q0104: I'm about to upgrade to a new Exim release. Do I need to ensure the
1635 spool is empty, or take any other special action?
1636
1637A0104: It depends on where you are coming from.
1638
1639 (1) If you are changing to release 4.00 or later from a release prior to
1640 4.00, you will need to make changes to the run time configuration file.
1641 See the file \(doc/Exim4.upgrade)\ for details. If you are coming from
1642 before release 3.00, you should also see \(doc/Exim3.upgrade)\.
1643
1644 (2) If you are upgrading from an Exim 4 release to a later release, you
1645 do not need to take special action. New releases are made backwards
1646 compatible with old spool files and hints databases, so that upgrading
1647 can be done on a running system. All that should be necessary is to
1648 install a new binary and then HUP the daemon.
1649
8e26e4bf
PH
1650 \**Warning**\: If you have changed the release of your DBM library, so
1651 that your new Exim is linked with a different release than the old one,
1652 you may encounter errors when Exim attempts to access the old hints
1653 databases. See Q0055.
1654
495ae4b0
PH
1655
1656Q0105: What does the error \*install-info: command not found*\ mean?
1657
1658A0105: You have set \\INFO_DIRECTORY\\ in your \(Local/Makefile)\, and Exim is trying
1659 to install the Texinfo documentation, but cannot find the command called
1660 \(install-info)\. If you have a version of Texinfo prior to 3.9, you
1661 should upgrade. Otherwise, check your installation of Texinfo to see why
1662 the \(install-info)\ command is not available.
1663
1664
1665Q0106: Exim doesn't seem to be recognizing my operating system type correctly,
1666 and so is failing to build.
1667
1668A0106: Run the command \"scripts/os-type -generic"\. The output should be one of
1669 the known OS types, and should correspond to your operating system. You
1670 can see which OS are supported by obeying \"ls OS/Makefile-*"\ and looking
1671 at the file name suffixes.
1672
1673 If there is a discrepancy, it means that the script is failing to
1674 interpret the output from the \"uname"\ command correctly, or that the
1675 output is wrong. Meanwhile, you can build Exim by obeying
1676
1677==> EXIM_OSTYPE=xxxx make
1678
1679 instead of just \"make"\, provided you are running a Bourne-compatible
1680 shell, or otherwise by setting \\EXIM_OSTYPE\\ correctly in your
1681 environment. It is probably best to start again from a clean
1682 distribution, to avoid any wreckage left over from the failed attempt.
1683
1684
1685Q0107: Exim fails to build, complaining about the absence of the \"killpg"\
1686 function.
1687
1688A0107: This function should be present in all modern flavours of Unix. If you
1689 are using an older version, you should be able to get round the problem
1690 by inserting
1691
1692==> #define killpg(pgid,sig) kill(-(pgid),sig)
1693
1694 into the file called \(OS/os.h-xxx)\, where xxx identifies your operating
1695 system, and is the output of the command \"scripts/os-type -generic"\.
1696
1697
1698Q0108: I'm getting an unresolved symbol \"ldap_is_ldap_url"\ when trying to build
1699 Exim.
1700
1701A0108: You must have specified \"LOOKUP_LDAP=yes"\ in the configuration. Have you
1702 remembered to set \"-lldap"\ somewhere (e.g. in \\LOOKUP_LIBS\\)? You need that
1703 in order to get the LDAP library scanned when linking.
1704
1705
1706Q0109: I'm getting an unresolved symbol \"mysql_close"\ when trying to build Exim.
1707
1708A0109: You must have specified \"LOOKUP_MYSQL=yes"\ in the configuration. Have you
1709 remembered to set \"-lmysqlclient"\ somewhere (e.g. in \\LOOKUP_LIBS\\)? You
1710 need that in order to get the MySQL library scanned when linking.
1711
1712
1713Q0110: I'm trying to build Exim with PAM support. I have included \"-lpam"\ in
1714 \\EXTRALIBS\\, but I'm still getting a linking error:
1715
1716==> /lib/libpam.so: undefined reference to `dlerror'
1717 /lib/libpam.so: undefined reference to `dlclose'
1718 /lib/libpam.so: undefined reference to `dlopen'
1719 /lib/libpam.so: undefined reference to `dlsym'
1720
1721A0110: Add \"-ldl"\ to \\EXTRALIBS\\. In some systems these dynamic loading functions
1722 are in their own library.
1723
1724
1725Q0111: I'm getting the error \*db.h: No such file or directory*\ when I try to
1726 build Exim.
1727
1728A0111: This problem has been seen with RedHat 7.0, but could also happen in
1729 other environments. If your system is using the DB library, you
1730 need to install the DB development package in order to build Exim.
1731 The package is called something like \"db3-devel-3.1.14-16.i386.rpm"\ for
1732 Linux systems, but you should check which version of DB you have
1733 installed (current releases are DB 4).
1734
1735
1736Q0112: I'm getting the error \*/usr/bin/ld: cannot find -ldb*\ when I try to
1737 build Exim.
1738
1739A0112: This is probably the same problem as Q0111.
1740
1741
1742Q0113: I've compiled Exim and I've managed to start it but there was one
1743 problem - it always complained that \(libmsqlclient.so.10)\ was not found,
1744 even though this file is in \(/usr/local/lib/mysql/)\.
1745
1746A0113: Solaris: ensure you have this in your \(Local/Makefile)\:
1747
1748==> LOOKUP_LIBS=-L/usr/local/lib/mysql -R/usr/local/lib/mysql
1749
1750 Net/Open/FreeBSD: Run this command (or ensure it gets run automatically
1751 at boot time):
1752
1753==> ldconfig -m /usr/local/lib/mysql
1754
1755 Linux: add \(/usr/local/lib/mysql)\ to \(/etc/ld.so.conf)\ and re-run \(ldconfig)\.
1756 Alternatively, add
1757
1758==> -Wl,-rpath -Wl,/usr/local/lib/mysql
1759
1760 to EXTRA_LIBS and then re-link (this is similar to the Solaris solution
1761 above). This will probably also work on other systems that use GNU
1762 Binutils.
1763
1764
1765Q0114: How can I remove Sendmail from my system? I've built Exim and run \"make
1766 install"\, but it still doesn't seem to be fully operational.
1767
1768A0114: If you are running FreeBSD, see Q9201. Otherwise, you need to arrange
1769 that whichever of the paths \(/usr/sbin/sendmail)\ or \(/usr/lib/sendmail)\
1770 exists on your system is changed to refer to Exim. For example, you
1771 could use these commands (as \/root/\):
1772
1773==> mv /usr/sbin/sendmail /usr/sbin/sendmail.original
1774 chmod u-s /usr/sbin/sendmail.original
1775 ln -s /path/to/exim /usr/sbin/sendmail
1776
1777 The second command removes the setuid privilege from the old MTA, as a
1778 general safety precaution. In the third command, substitute the actual
1779 path to the Exim binary for \(/path/to/exim)\.
1780
1781
1782Q0115: What does \*Can't open \(../scripts/newer)\: No such file or directory*\
1783 mean? I got it while trying to build Exim.
1784
1785A0115: You are using FreeBSD, or another OS that has a \^make^\ command which
1786 tries to optimize the running of commands. Exim's \(Makefile)\ contains
1787 targets with sequential commands like this:
1788
1789==> buildpcre:
1790 @cd pcre; $(MAKE) SHELL=$(SHELL) AR="$(AR)" $(MFLAGS) CC="$(CC)" \
1791 CFLAGS="$(CFLAGS) $(PCRE_CFLAGS)" \
1792 RANLIB="$(RANLIB)" HDRS="$(PHDRS)" \
1793 INCLUDE="$(INCLUDE) $(IPV6_INCLUDE) $(TLS_INCLUDE)"
1794 @if $(SHELL) $(SCRIPTS)/newer pcre/libpcre.a exim; then \
1795 /bin/rm -f exim eximon.bin; fi
1796
1797 The second command assumes that the \"cd pcre"\ in the first command is
1798 no longer in effect. If you have \"-j3"\ in your default set of
1799 \"MAKEFLAGS"\, FreeBSD \^make^\ tries to optimize, and ends up up with both
1800 commands in the same shell process. The result is that \"$(SCRIPTS)"\
1801 (which has a value of \"../scripts"\) is not found.
1802
1803 The simplest solution is to force \^make^\ to use backwards compatibility
1804 mode with each command in its own shell, by using the \-B\ flag. To
1805 ensure that this happens throughout the build, it's best to export it in
1806 your environment:
1807
f0884f39
PH
1808==> MAKEFLAGS='-B'
1809 export MAKEFLAGS
1810 make
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1811
1812
1813Q0116: I have tried to build Exim with Berkeley DB 3 and 4, but I always get
1814 errors.
1815
1816A0116: One common problem, especially when you have several different versions
1817 of BDB installed on the same host, is that the header files and library
1818 files for BDB are not in a standard place. You therefore need to tell
1819 Exim where they are, by setting INCLUDE and DBMLIB in your
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1820 \(Local/Makefile)\. For example, you could use this when you want to
1821 build with DB 4.1:
495ae4b0 1822
8e26e4bf
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1823==> INCLUDE=-I/usr/local/include/db-4.1
1824 DBMLIB=/usr/local/lib/db-4.1/libdb.a
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1825
1826 Specifying the complete library file like this will cause it to be
1827 statically linked with Exim. You'll have to check to see where these
1828 files are on your system. For example, on FreeBSD 5, the header is in
1829 \(/usr/local/include/db4)\ and the library is in \(/usr/local/lib)\ and
1830 called \(libdb4)\. In that environment, you could use:
1831
1832==> INCLUDE=-I/usr/local/include/db4
1833 DBMLIB=-L/usr/local/lib -ldb4
1834
1835 This time, DBMLIB is specifying the library directory (\(/usr/local/lib)\)
1836 and the name of the library (\(db4)\) separately. The name of the actual
1837 library file is \(/usr/local/lib/libdb4.something)\. If the library was
1838 compiled for dynamic linking, that will be used.
1839
1840
1841Q0117: Is there a quick walk-through of an Exim install from source anywhere?
1842
1843A0117: Here! This is a contribution from a RedHat user, somewhat edited. On
1844 other operating systems things may be slightly different, but the
1845 general approach is the same.
1846
1847 (1) Install the db needed for Exim. This needs to be done first if you
1848 don't have a DBM library installed. Go to \?http://www.sleepycat.com?\
1849 and download \(db-4.1.25.tar.gz)\, or whatever the current release is.
1850 Then:
1851
1852==> gunzip db-4.1.25.tar.gz
1853 tar -xvf db-4.1.25.tar
1854 cd db-4.1.25
1855 cd build_unix
1856 ../dist/configure
1857 make
1858 make install
1859
1860 (2) Add a user for use by Exim, unless you want to use an existing user
1861 such as \/mail/\:
1862
1863==> adduser exim
1864
1865 (3) Now you can prepare to build Exim. Go to \?http://www.exim.org?\ or
1866 one of its mirrors, or the master ftp site
1867 \?ftp://ftp.csx.cam.ac.uk/pub/software/email/exim/exim4?\, and download
1868 \(exim-4.20.tar.gz)\ or whatever the current release is. Then:
1869
1870==> gunzip exim-4.20.tar.gz
1871 tar -xvf exim-4.20.tar
1872 cd exim-4.20
1873 cp src/EDITME Local/Makefile
1874 cp exim_monitor/EDITME Local/eximon.conf
1875
1876 (4) Edit \(Local/Makefile)\:
1877
1878 Comment out EXIM_MONITOR= unless you want to install the Exim
1879 monitor (it requires X-windows).
1880
1881 Set the user you want Exim to use for itself:
1882
1883==> EXIM_USER=exim
1884
1885 If your DBM library is Berkeley DB, set up to use its native interface:
1886
1887==> USE_DB=yes
1888
1889 Make sure Exim's build can find the DBM library and its headers. If
1890 you've installed Berkeley DB 4 you'll need to have settings like this
1891 in \(Local/Makefile)\:
1892
1893==> INCLUDE=-I/usr/local/BerkeleyDB.4.1/include
1894 DBMLIB=/usr/local/BerkeleyDB.4.1/lib/libdb.a
1895
1896 (Check that the first directory contains the db.h file and that the
1897 second library exists.)
1898
1899 You don't need to change anything else, but you might want to review
1900 the default settings in the ``must specify'' section.
1901
1902 (4) Build Exim by running the \/make/\ command.
1903
1904 (5) Install Exim by running, as \/root/\:
1905
1906==> make install
1907
8e26e4bf 1908 You must be \/root/\ to do this. You do not have to be root for any of
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1909 the previous building activity.
1910
1911 (6) Run some tests on Exim; see if it will do local and remote
1912 deliveries. Change the configuration if necessary (for example,
1913 uncommenting \group\ on the \%local_delivery%\ transport if you don't
1914 use a ``sticky bit'' directory).
1915
1916 (7) Change Sendmail to Exim (of course you need to have had Sendmail
1917 installed to do this).
1918
1919==> /etc/init.d/sendmail stop
1920 mv /usr/sbin/sendmail /usr/sbin/sendmail.org
1921 ln -s /usr/exim/bin/exim /usr/sbin/sendmail
1922 /etc/init.d/sendmail start
1923
1924 (8) Check the Exim log. Either use the Exim monitor, or:
1925
1926==> tail -f /var/spool/exim/log/mainlog
1927
1928
1929Q0118: I've set \"LOOKUP_INCLUDE=-I/client/include"\ in Local/Makefile, but the
1930 compilation of \^exim_dumpdb^\ is ignoring this option and failing. Why?
1931
1932A0118: LOOKUP_INCLUDE is the special include file for lookup modules in Exim
1933 (e.g. mysql, LDAP). Confusingly, it doesn't apply to basic DBM code
1934 which is used also for other things. Try setting INCLUDE and DBMLIB
1935 instead. For example:
1936
1937==> USE_DB=yes
1938 INCLUDE=-I/client/include
1939 DBMLIB=/client/lib/libdb.a
1940
1941
1942Q0119: I know there are some 3rd-party patches for Exim, for exiscan and
1943 other things. Where are they?
1944
1945A0119: Exiscan is at \?http://duncanthrax.net/exiscan-acl/?\.
1946[[br]]
1947 Scanexi is at \?http://w1.231.telia.com/~u23107873/scanexi.html?\
1948[[br]]
1949 A sample \^^local_scan()^^\ function for interfacing to \^uvscan^\ is
1950 at \?http://www.dcs.qmul.ac.uk/~mb/local_scan/?\.
1951[[br]]
1952 An interface to SpamAssassin at SMTP time is at
1953 \?http://marc.merlins.org/linux/exim/sa.html?\.
1954[[br]]
1955 A mini-HOWTO (PDF file) about scanning and virus scanning, and some RPMs
1956 can be found at \?http://www.timj.co.uk/linux/exim.php?\.
1957
1958
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1959Q0120: I'm trying to compile with LOOKUP_WHOSON, but I keep getting \*In
1960 function `whoson_find': undefined reference to `wso_query'*\.
1961
1962A0120: Try adding \"-lwhoson"\ to your LOOKUP_LIBS setting in \(Local/Makefile)\.
1963
1964
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1965
19662. ROUTING IN GENERAL
1967
1968Q0201: How can I arrange that messages larger than some limit are handled by
1969 a special router?
1970
1971A0201: You can use a \condition\ option on the router line this:
1972
1973==> condition = ${if >{$message_size}{100K}{yes}{no}}
1974
1975
1976Q0202: Can I specify a list of domains to explicitly reject?
1977
1978A0202: Set up a named domain list containing the domains in the first section
1979 of the configuration, for example:
1980
1981==> domainlist reject_domains = list:of:domains:to:reject
1982
1983 You can use this list in an ACL to reject any SMTP recipients in those
1984 domains. You can also give a customized error message, like this:
1985
1986==> deny message = The domain $domain is no longer supported
1987 domains = +reject_domains
1988
1989 If you also want to reject these domains in messages that are submitted
1990 from the command line (not using SMTP), you need to set up a router to
1991 do it, like this:
1992
1993==> reject_domains:
1994 driver = redirect
1995 domains = +reject_domains
1996 allow_fail
1997 data = :fail: The domain $domain is no longer supported
1998
1999
2000Q0203: How can I arrange to do my own qualification of non-fully-qualified
2001 domains, and then pass them on to the next router?
2002
2003A0203: If you have some list of domains that you want to qualify, you can do
2004 this using a redirect router. For example,
2005
2006==> qualify:
2007 driver = redirect
2008 domains = *.a.b
2009 data = ${quote:$local_part}@$domain.c.com
2010
2011 This adds \".c.com"\ to any domain that matches \"*.a.b"\.
2012 If you want to do this in conjunction with a \%dnslookup%\ router, the
2013 \widen_domains\ option of that router may be another way of achieving
2014 what you want.
2015
2016
2017Q0204: Every system has a \"nobody"\ account under which httpd etc run. I would
2018 like to know how to restrict mail which comes from that account to users
2019 on that host only.
2020
2021A0204: Set up a first router like this:
2022
2023==> fail_nobody:
2024 driver = redirect
2025 senders = nobody@your.domain
2026 domains = ! +local_domains
2027 allow_fail
2028 data = :fail: Nobody may not mail off-site
2029
2030 This assumes you have defined \+local_domains\ as in the default
2031 configuration.
2032
2033
2034Q0205: How can I get Exim to deliver to me locally and everyone else at the same
2035 domain via SMTP to the MX record specified host?
2036
2037A0205: Create an \%accept%\ router to pick off the one address and pass it to
2038 an appropriate transport. Put this router before the one that does MX
2039 routing:
2040
2041==> me:
2042 driver = accept
2043 domains = dom.com
2044 local_parts = me
2045 transport = local_delivery
2046
2047 In the transport you will have to specify the \user\ option. An
2048 alternative way of doing this is to add a condition to the router that
2049 does MX lookups to make it skip your address. Subsequent routers can then
2050 deliver your address locally. You'll need a condition like this:
2051
2052==> condition = \
2053 ${if and {{eq{$domain}{dom.com}}{eq{$local_part}{me}}}{no}{yes}}
2054
2055
2056Q0206: How can I get Exim to deliver certain domains to a different SMTP port
2057 on my local host?
2058
2059A0206: You must set up a special \%smtp%\ transport, where you can specify the
2060 \port\ option, and then set up a router to route the domains to that
2061 transport. There are two possibilities for specifying the host:
2062
2063 (1) If you use a \%manualroute%\ router, you can specify the local host
2064 in the router options. You must also set
2065
2066==> self = send
2067
2068 so that it does not object to sending to the local host.
2069
2070 (2) If you use a router that cannot specify hosts (for example, an
2071 \%accept%\ router with appropriate conditions), you have to specify
2072 the host using the \hosts\ option of the transport. In this case,
2073 you must also set \allow_localhost\ on the transport.
2074
2075
2076Q0207: Why does Exim lower-case the local-part of a non-local domain when
2077 routing?
2078
2079A0207: Because \caseful_local_part\ is not set (in the default configuration)
2080 for the \%dnslookup%\ router. This does not matter because the local
2081 part takes no part in the routing, and the actual local part that is
2082 sent out in the RCPT command is always the original local part.
2083
2084
8e26e4bf
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2085Q0208: I can't get a lookup to work in a domain list. I'm trying this:
2086
2087==> domainlist local_domains = @:localhost:${lookup pgsql{SELECT ...
2088
2089A0208: Does the lookup return a colon separated list of domains? If not, you
2090 are using the wrong kind of lookup. The most common way of using a
2091 lookup in a domain list is something like this:
2092
2093==> domainlist local_domains = @:localhost:pgsql;SELECT ...
2094
2095 Using that syntax, if the query succeeds, the domain is considered to be
2096 in the list. The value that is returned is not relevant.
2097
2098
495ae4b0
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2099
21003. ROUTING TO REMOTE HOSTS
2101
2102Q0301: What do \*lowest numbered MX record points to local host*\ and \*remote
2103 host address is the local host*\ mean?
2104
2105A0301: They mean exactly what they say. Exim expected to route an address to a
2106 remote host, but the IP address it obtained from a router was for the
2107 local host. If you really do want to send over TCP/IP to the local host
2108 (to a different version of Exim or another MTA, for example), see Q0206.
2109
2110 More commonly, these errors arise when Exim thinks it is routing some
2111 foreign domain. For example, the router configuration causes Exim to
2112 look up the domain in the DNS, but when Exim examines the DNS output,
2113 either the lowest numbered MX record points at the local host, or there
2114 are no MX records, and the address record for the domain contains an
2115 IP address that belongs to the local host.
2116
2117 There has been a rash of instances of domains being deliberately set up
2118 with MX records pointing to \"localhost"\ (or other names with A records
2119 that specify 127.0.0.1), which causes this behaviour. You can use the
2120 \ignore_target_hosts\ option to get Exim to ignore these records. The
2121 default contiguration does this. For more discussion, see Q0319. For
2122 other cases:
2123
2124 (1) If the domain is meant to be handled as a local domain, there
2125 is a problem with the configuration, because it should not then have
2126 been looked up in the DNS. Check the \domains\ settings on your
2127 routers.
2128
2129 (2) If the domain is one for which the local host is providing a
2130 relaying service (called ``mail hubbing''), possibly as part of a
2131 firewall, you need to set up a router to tell Exim where to send
2132 messages addressed to this domain, because the DNS directs them to
2133 the local host. You should put a router like this one before the one
2134 that does DNS lookups:
2135
2136==> hubbed_hosts:
2137 driver = manualroute
2138 transport = remote_smtp
2139 route_list = see discussion below
2140
2141 The contents of the \route_list\ option depend on how many hosts you
2142 are hubbing for, and how their names are related to the domain name.
2143 Suppose the local host is a firewall, and all the domains in
2144 \(*.foo.bar)\ have MX records pointing to it, and each domain
2145 corresponds to a host of the same name. Then the setting could be
2146
2147==> route_list = *.foo.bar $domain
2148
2149 If there isn't a convenient relationship between the domain names
2150 and the host names, you either have to list each domain separately,
2151 or use a lookup expansion to look up the host from the domain, or
2152 put the routing information in a file and use the \route_data\
2153 option with a lookup expansion.
2154
2155 (3) If neither (1) nor (2) is the case, the lowest numbered MX record or
2156 the address record for the domain should not be pointing to your
2157 host. You should arrange to get the DNS mended.
2158
2159
2160Q0302: Why does Exim say \*all relevant MX records point to non-existent hosts*\
2161 when MX records point to IP addresses?
2162
2163A0302: MX records cannot point to IP addresses. They are defined to point to
2164 host names, so Exim always interprets them that way. (An IP address is a
2165 syntactically valid host name.) The DNS for the domain you are having
2166 problems with is misconfigured.
2167
2168 However, it appears that more and more DNS zones are breaking the rules
2169 and putting IP addresses on the RHS of MX records. Exim follows the
2170 rules and rejects this, but other MTAs do support it, so the
2171 \allow_mx_to_ip\ was regretfully added at release 3.14 to permit this
2172 heinous activity.
2173
2174
2175Q0303: How do I configure Exim to send all messages to a central server? I
2176 don't want to do any local deliveries at all on this host.
2177
2178A0303: Use this as your first and only router:
2179
2180==> send_to_gateway:
2181 driver = manualroute
2182 transport = remote_smtp
2183 route_list = * central.server.host
2184
2185
2186Q0304: How do I configure Exim to send all non-local mail to a gateway host?
2187
2188A0304: Replace the \%dnslookup%\ router in the default configuration with the
2189 following:
2190
2191==> send_to_gateway:
2192 driver = manualroute
2193 domains = !+local_domains
2194 transport = remote_smtp
2195 route_list = * gate.way.host
2196
2197 If there are several hosts you can send to, you can specify them as a
2198 colon-separated list.
2199
2200
2201Q0305: How can I arrange for mail on my local network to be delivered directly
2202 to the relevant hosts, but all other mail to be sent to my ISP's mail
2203 server? The local hosts are all DNS-registered and behave like normal
2204 Internet hosts.
2205
2206A0305: Set up a first router to pick off all the domains for your local
2207 network. There are several ways you might do this. For example
2208
2209==> local_network:
2210 driver = dnslookup
2211 transport = remote_smtp
2212 domains = *.mydomain.com
2213
2214 This does a perfectly conventional DNS routing operation, but only for
2215 the domains that match \(*.mydomain.com)\. Follow this with a `smart
2216 host' router:
2217
2218==> internet:
2219 driver = manualroute
2220 domains = !+local_domains
2221 transport = remote_smtp
2222 route_list = * mail.isp.net
2223
2224 This routes any other non-local domains to the smart host.
2225
2226
2227Q0306: How do I configure Exim to send all non-local mail to a central server
2228 if it cannot be immediately delivered by my host? I don't want to have
2229 queued mail waiting on my host.
2230
2231A0306: Add to the \%remote_smtp%\ transport the following:
2232
2233==> fallback_hosts = central.server.name(s)
2234
2235 If there are several names, they must be separated by colons.
2236
2237
2238Q0307: The \route_list\ setting \"^foo$:^bar$ $domain"\ in a \%manualroute%\
2239 router does not work.
2240
2241A0307: The first thing in a \route_list\ item is a single pattern, not a list of
2242 patterns. You need to write that as \"^(foo|bar)$ $domain"\.
2243 Alternatively, you could use several items and write
2244
2245==> route_list = foo $domain; bar $domain
2246
2247 Note the semicolon separator. This is because the second thing in each
8e26e4bf 2248 item can itself be a colon-separated list of hosts.
495ae4b0
PH
2249
2250
2251Q0308: I have a domain for which some local parts must be delivered locally,
2252 but the remainder are to be treated like any other remote addresses.
2253
2254A0308: One possible way of doing this is as follows: Assuming you are using a
2255 configuration that is similar to the default one, first exclude your
2256 domain from the first router by changing it to look like this:
2257
2258==> non_special_remote:
2259 driver = dnslookup
2260 domains = ! +local_domains : ! special.domain
2261 transport = remote_smtp
2262 ignore_target_hosts = 127.0.0.0/8
2263 no_more
2264
8e26e4bf 2265 Then add a second router to handle the local parts that are not to
495ae4b0
PH
2266 be delivered locally:
2267
2268==> special_remote:
2269 driver = dnslookup
2270 domains = special.domain
2271 local_parts = ! lsearch;/list/of/special/localparts
2272 transport = remote_smtp
2273 ignore_target_hosts = 127.0.0.0/8
2274 no_more
2275
2276 The remaining local parts will fall through to the remaining routers,
2277 which can delivery them locally.
2278
2279
2280Q0309: How can I configure Exim on a firewall machine so that if mail arrives
2281 addressed to a domain whose MX points to the firewall, it is forwarded
2282 to the internal mail server, without having to have a list of all the
2283 domains involved?
2284
2285A0309: As your first router, have the standard \%dnslookup%\ router from the
2286 default configuration, with the added option
2287
2288==> self = pass
2289
2290 This will handle all domains whose lowest numbered MX records do not
2291 point to your host. Because of the \no_more\ setting, if it encounters
2292 an unknown domain, routing will fail. However, if it hits a domain whose
2293 lowest numbered MX points to your host, the \self\ option comes into
2294 play, and overrides \no_more\. The \"pass"\ setting causes it to pass
2295 the address on to the next router. (The default causes it to generate an
2296 error.)
2297
2298 The only non-local domains that reach the second router are those with
2299 MX records pointing to the local host. Set it up to send them to the
2300 internal mail server like this:
2301
2302==> internal:
2303 driver = manualroute
2304 domains = ! +local_domains
2305 transport = remote_smtp
2306 route_list = * internal.server
2307
2308
2309Q0310: If a DNS lookup returns no MX records why doesn't Exim just bin the
2310 message?
2311
2312A0310: If a DNS lookup returns no MXs, Exim looks for an address record, in
2313 accordance with the rules that are defined in the RFCs. If you want to
2314 break the rules, you can set \mx_domains\ in the \%dnslookup%\ router, but
2315 you will cut yourself off from those sites (and there still seem to be
2316 plenty) who do not set up MX records.
2317
2318
2319Q0311: When a DNS lookup for MX records fails to complete, why doesn't Exim
2320 send the messsage to the host defined by the A record?
2321
2322A0311: The RFCs are quite clear on this. Only if it is known that there are no
2323 MX records is an MTA allowed to make use of the A record. When an MX
2324 lookup fails to complete, Exim does not know whether there are any MX
2325 records or not. There seem to be some name servers (or some
2326 configurations of some name servers) that give a ``server fail'' error when
2327 asked for a non-existent MX record. Exim uses standard resolver calls,
2328 which unfortunately do not distinguish between this case and a timeout,
2329 so all Exim can do is try again later.
2330
2331
2332Q0312: Is it possible to use a conditional expression for the host item in a
2333 \route_list\ for \%manualroute%\ router? I tried the following, but it
2334 doesn't work:
2335
2336==> route_list = * ${if match{$header_from:}{\N.*\.usa\.net$\N} \
2337 {<smarthost1>}{<smarthost2>}
2338
2339A0312: The problem is that the second item in \route_list\ contains white
2340 space, which means that it gets terminated prematurely. To avoid this,
2341 you must put the second item in quotes:
2342
2343==> route_list = * "${if match{$header_from:}{\N.*\.usa\.net$\N} \
2344 {<smarthost1>}{<smarthost2>}}"
2345
2346
2347Q0313: I send all external mail to a smart host, but this means that bad
2348 addresses also get passed to the smart host. Can I avoid this?
2349
2350A0313: Assuming you have DNS availability, set up a conventional \%dnslookup%\
2351 router to do the routing, but in the \%remote_smtp%\ transport set this:
2352
2353==> hosts = your.smart.host
2354 hosts_override
2355
2356 This will override the hosts that the router finds so that everything
2357 goes to the smart host, but any non-existent domains will be failed by
2358 the router.
2359
2360
2361Q0314: I have a really annoying intermittent problem where attempts to mail to
2362 valid sites are rejected with \*unknown mail domain*\. This only happens a
2363 few times a day and there is no particular pattern to the sites it
2364 rejects. If I try to lookup the same domain a few minutes later then it
2365 is OK.
2366
2367A0314: This is almost certainly a problem with the DNS resolver or the the
2368 domain's name servers.
2369
2370 (1) Have you linked Exim against the newest DNS resolver library that
2371 comes with Bind? If you are using SunOS4 that may be your problem, as
2372 the resolver that comes with that OS is known to be buggy and to give
2373 intermittent false negatives.
2374
2375 (2) Effects like this are sometimes seen if a domain's name servers get
2376 out of step with each other.
2377
2378
2379Q0315: I'd like route all mail with addresses that can't be resolved (the DNS
2380 lookup times out) to a relay machine.
2381
2382A0315: Set \pass_on_timeout\ on your \%dnslookup%\ router, and add below it a
2383 \%manualroute%\ router that routes all relevant domains to the relay.
2384
2385
2386Q0316: I would like to forward all incoming email for a particular domain to
2387 another host via SMTP. Whereabouts would I configure that?
2388
2389A0316: Use this as your first router:
2390
2391==> special:
2392 driver = manualroute
2393 transport = remote_smtp
2394 route_list = the.particular.domain the.other.host
2395
2396 You will also need to adjust the ACL for incoming SMTP so that this
2397 domain is accepted for relaying. If you are using the default
2398 configuration, there is a domain list called \relay_domains\ that is
2399 set up for this.
2400
2401
2402Q0317: What I'd like to do is have alternative smart hosts, where the one to be
2403 used is determined by which ISP I'm connected to.
2404
2405A0317: The simplest way to do this is to arrange for the name of the smart host
2406 du jour to be placed in a file when you connect, say \(/etc/smarthost)\.
2407 Then you can read this file from a \%manualroute%\ router like this:
2408
2409==> smarthost:
2410 driver = manualroute
2411 transport = remote_smtp
2412 route_list = * ${readfile{/etc/smarthost}{}}
2413
2414 The second argument of the \"readfile"\ item is a string that replaces
2415 any newline characters in the file (in this case, with nothing).
2416 By keeping the data out of the main configuration file, you avoid having
2417 to HUP the daemon when it changes.
2418
2419
2420Q0318: Exim won't route to a host with no MX record.
2421
2422A0318: More than one thing may cause this.
2423
2424 (1) Are you sure there really is no MX record? Sometimes a typo results
2425 in a malformed MX record in the zone file, in which case some name
2426 servers give a SERVFAIL error rather than NXDOMAIN. Exim has to treat
2427 this as a temporary error, so it can't go on to look for address records.
2428 You can check for this state using one of the DNS interrogation commands,
2429 such as \(nslookup)\, \(host)\, or \(dig)\.
2430
2431 (2) Is there a wildcard MX record for \(your)\ domain? Is the
2432 \search_parents\ option on in your \%dnslookup%\ router? If the answer to
2433 both these questions is ``yes'', that is the cause of the problem. When
2434 the DNS resolver fails to find the MX record, it tries adding on your
2435 domain if \search_parents\ is true, and thereby finds your wildcard MX
2436 record. For example:
2437
2438 . There is a wildcard MX record for \(*.a.b.c)\.
2439
2440 . There is a host called \(x.y.z)\ that has an A record and no MX record.
2441
2442 . Somebody on the host \(m.a.b.c)\ domain tries to mail to \(user@x.y.z)\.
2443
2444 . Exim calls the DNS to look for an MX record for \(x.y.z)\.
2445
2446 . The DNS doesn't find any MX record. Because \search_parents\ is true,
2447 it then tries searching the current host's parent domain, so it
2448 looks for \(x.y.z.a.b.c)\ and picks up the wildcard MX record.
2449
2450 Setting \search_parents\ false makes this case work while retaining the
2451 wildcard MX record. However, anybody on the host \(m.a.b.c)\ who mails to
2452 \(user@n.a)\ (expecting it to go to \(user@n.a.b.c)\) now has a problem. The
2453 \widen_domains\ option of the \%dnslookup%\ router may be helpful in this
2454 circumstance.
2455
2456
2457Q0319: I have some mails on my queues that are sticking around longer than
2458 the retry time indicates they should. They are all getting frozen
2459 because some remote admin has set their MX record to 127.0.0.1.
2460
2461A0319: The admin in question is an idiot. Exim will always freeze such messages
2462 because they are apparently routed to the local host. To bounce these
2463 messages immediately, set
2464
2465==> ignore_target_hosts = 127.0.0.1
2466
2467 on the \%dnslookup%\ router. This causes Exim to completely ignore any hosts
2468 with that IP address. In fact, there are quite a number of IP addresses
2469 that should never be used. Here is a suggested configuration list for
2470 the IPv4 ones:
2471
2472==> # Don't allow domains whose single MX (or A) record is a
2473 # "special-use IPv4 address", as listed in RFC 3330.
2474 ignore_target_hosts = \
f0884f39
PH
2475 # Hosts on "this network"; RFC 1700 (page 4) states that these
2476 # are only allowed as source addresses
2477 0.0.0.0/8 : \
2478 # Private networks, RFC 1918
2479 10.0.0.0/8 : 172.16.0.0/12 : 192.168.0.0/16 : \
2480 # Internet host loopback address, RFC 1700 (page 5)
2481 127.0.0.0/8 : \
2482 # "Link local" block
2483 169.254.0.0/16 : \
2484 # "TEST-NET" - should not appear on the public Internet
2485 192.0.2.0/24 : \
2486 # 6to4 relay anycast addresses, RFC 3068
2487 192.88.99.0/24 : \
2488 # Network interconnect device benchmark testing, RFC 2544
2489 198.18.0.0/15 : \
2490 # Multicast addresses, RFC 3171
2491 224.0.0.0/4 : \
2492 # Reserved for future use, RFC 1700 (page 4)
2493 240.0.0.0/4
495ae4b0
PH
2494
2495
2496Q0320: How can I arrange for all mail to \*user@some.domain*\ to be forwarded
2497 to \*user@other.domain*\?
2498
2499A0320: Put this as your first router:
2500
2501==> forward:
2502 driver = redirect
2503 domains = some.domain
2504 data = ${quote:$local_part}@other.domain
2505
2506
2507Q0321: How can I tell an Exim router to use only IPv4 or only IPv6 addresses
2508 when it finds both types in the DNS?
2509
2510A0321: You can do this by making it ignore the addresses you don't want. This
2511 example ignores all IPv6 addresses and all IPv4 addresses in the 127
2512 network:
2513
2514==> ignore_target_hosts = <; 0000::0000/0 ; 127.0.0.0/8
2515
2516 To ignore all IPv4 addresses, use
2517
2518==> ignore_target_hosts = 0.0.0.0/0
2519
2520 See Q0319 for a general discussion of \ignore_target_hosts\.
2521
2522
2523Q0322: How can I reroute all messages bound for 192.168.10.0 and 10.0.0.0 to
2524 a specific mail server?
2525
2526A0322: That is an odd requirement. However, there is an obscure feature in
2527 Exim, originally implemented for packet radio people, that perhaps can
2528 help. Check out the \translate_ip_address\ generic router option.
2529
2530
2531
25324. ROUTING FOR LOCAL DELIVERY
2533
2534Q0401: I need to have any mail for \(virt.dom.ain)\ that doesn't match one of the
2535 aliases in \(/usr/lib/aliases.virt)\ delivered to a particular address, for
2536 example, \(postmaster@virt.dom.ain)\.
2537
2538A0401: Adding an asterisk to a search type causes Exim to look up ``*'' when the
2539 normal lookup fails. So if your aliasing router is something like this:
2540
2541==> virtual:
2542 driver = redirect
2543 domains = virt.dom.ain
2544 data = ${lookup{$local_part}lsearch{/usr/lib/aliases.virt}}
2545 no_more
2546
2547 you should change \"lsearch"\ to \"lsearch*"\, and put this in the alias
2548 file:
2549
2550==> *: postmaster@virt.dom.ain
2551
2552 This solution has the feature that if there are several unknown
2553 addresses in the same message, only one copy gets sent to the
2554 postmaster, because of Exim's normal de-duplication rules.
2555
2556 NOTE: This solution works only if there is also an entry for \(postmaster)\
2557 in the alias file, ultimately resolving to an address that is not in
2558 \(virt.dom.ain)\. See also Q0434.
2559
2560
2561Q0402: How do I arrange for all incoming email for \(*@some.domain)\ to go into one
2562 pop3 mail account? The customer doesn't want to add a list of specific
2563 local parts to the system.
2564
2565A0402: Set up a special transport that writes to the mailbox like this:
2566
2567==> special_transport:
2568 driver = appendfile
2569 file = /pop/mailbox
2570 envelope_to_add
2571 return_path_add
2572 delivery_date_add
2573 user = exim
2574
2575 The file will be written as the user \"exim"\. Then arrange to route all
2576 mail for that domain to that transport, with a router like this:
2577
2578==> special_router:
2579 driver = accept
2580 domains = some.domain
2581 transport = special_transport
2582
2583
2584Q0403: How do I configure Exim to send messages for unknown local users to a
2585 central server?
2586
2587A0403: Assuming you are using something like the default configuration, where
2588 local users are processed by the later routers, you should add the
2589 following router at the end:
2590
2591==> unknown:
2592 driver = manualroute
2593 transport = remote_smtp
2594 route_list = * server.host.name
2595 no_verify
2596
2597 However, you should if possible try to verify that the user is known on
2598 the central server before accepting the message in the first place. This
2599 can be done by making use of Exim's ``call forward'' facility.
2600
2601
2602Q0404: How can I arrange for messages submitted by (for example) Majordomo to
2603 be handled specially?
2604
2605A0404: You can use the \condition\ option on a router, with a setting such as
2606
2607==> condition = ${if and {{eq {$sender_host_address}{}} \
2608 {eq {$sender_ident}{majordom}}} {yes}{no}}
2609
2610 This first tests for a locally-submitted message, by ensuring there is
2611 no sending host address, and then it checks the identity of the user
2612 that ran the submitting process.
2613
2614
2615Q0405: On a host that accepts mail for several domains, do I have to use fully
2616 qualified addresses in \(/etc/aliases)\ or do I have to set up an alias
2617 file for each domain?
2618
2619A0405: You can do it either way. The default aliasing router contains this line:
2620
2621==> data = ${lookup{$local_part}lsearch{/etc/aliases}}
2622
2623 which is what does the actual lookup. To make it look up the complete
2624 address instead of just the local part, use
2625
2626==> data = ${lookup{$local_part@$domain}lsearch{/etc/aliases}}
2627
2628 If you want to use a separate file for each domain, use
2629
2630==> data = ${lookup{$local_part}lsearch{/etc/aliases/$domain}}
2631
2632
2633Q0406: Some of my users are using the \(.forward)\ to pipe to a shell command which
2634 appends to the user's INBOX. How can I forbid this?
2635
2636A0406: If you allow your users to run shells in pipes, you cannot control which
2637 commands they run or which files they write to. However, you should point
2638 out to them that writing to an INBOX by arbitrary commands is not
2639 interlocked with the MTA and MUAs, and is liable to mess up the contents
2640 of the file.
2641
2642 If a user simply wants to choose a specific file for the delivery of
2643 messages, this can be done by putting a file name in a \(.forward)\ file
2644 rather than using a pipe, or by using the \"save"\ command in an Exim
2645 filter file.
2646
2647 You can set \forbid_pipe\ on the router, but that will prevent them from
2648 running any pipe commands at all. Alternatively, you can restrict which
2649 commands they may run in their pipes by setting the \allow_commands\
2650 and/or \restrict_to_path\ options in the \%address_pipe%\ transport.
2651
2652
2653Q0407: How can I arrange for a default value when using a query-style lookup
2654 such as LDAP or NIS+ to handle aliases?
2655
2656A0407: Use a second query in the failure part of the original lookup, like
2657 this:
2658
2659==> data = ${lookup ldap\
2660 {ldap://x.y.z/l=yvr?aliasaddress?sub?(&(mail=$local_part@$domain))}\
2661 {$value}\
2662 {\
2663 ${lookup ldap \
2664 {ldap://x.y.z/l=yvr?aliasaddress?sub?(&(mail=default@$domain))}}\
2665 }}
2666
2667 Of course, if the default is a fixed value you can just include it
2668 directly.
2669
2670
2671Q0408: If I don't fully qualify the addresses in a virtual domain's alias file
2672 then mail to aliases which also match the local domain get delivered to
2673 the local domain.
2674
2675A0408: Set the \qualify_preserve_domain\ option on the \%redirect%\ router.
2676
2677
2678Q0409: I want mail for any local part at certain virtual domains to go
2679 to a single address for each domain.
2680
9c2b45c9 2681A0409: One way to do this is
495ae4b0
PH
2682
2683==> virtual:
2684 driver = redirect
2685 data = ${lookup{$domain}lsearch{/etc/virtual}}
2686
2687 The \(/etc/virtual)\ file contains a list of domains and the addresses to
2688 which their mail should be sent. For example:
2689
2690==> domain1: postmaster@some.where.else
2691 domain2: joe@xyz.plc
2692
2693 If the number of domains is large, using a DBM or cdb file would be more
2694 efficient. If the lookup fails to find the domain in the file, the value
2695 of the \data\ option is empty, causing the router to decline.
2696
2697
2698Q0410: How can I make Exim look in the alias NIS map instead of \(/etc/aliases)\?
2699
2700A0410: The default configuration does not use NIS (many hosts don't run it).
2701 You need to change this line in the \%system_aliases%\ router:
2702
2703==> data = ${lookup{$local_part}lsearch{/etc/aliases}}
2704
2705 Change it to
2706
2707==> data = ${lookup{$local_part}nis{mail.aliases}}
2708
2709 If you want to use \(/etc/aliases)\ as well as NIS, put this router (with
2710 a different name) before or after the default one, depending on which
2711 data source you want to take precedence.
2712
2713
2714Q0411: Why will Exim deliver a message locally to any username that is longer
2715 than 8 characters as long as the first 8 characters match one of the
2716 local usernames?
2717
2718A0411: The problem is in your operating system. Exim just calls the \^^getpwnam()^^\
2719 function to test a local part for being a local login name. It does not
2720 presume to guess the maximum length of user name for the underlying
2721 operating system. Many operating systems correctly reject names that are
2722 longer than the maximum length; yours is apparently deficient in this
2723 regard. To cope with such systems, Exim has an option called
2724 \max_user_name_length\ which you can set to the maximum allowed length.
2725
2726
2727Q0412: Why am I seeing the error \*bad mode (100664) for /home/test/.forward*\?
2728 I've looked through the documentation but can't see anything to suggest
2729 that Exim has to do anything other than read the \(.forward)\ file.
2730
2731A0412: For security, Exim checks for mode bits that shouldn't be set, by
2732 default 022. You can change this by setting the \modemask\ option of the
2733 \%redirect%\ router that is handling \(.forward)\ files.
2734
2735
2736Q0413: When a user's \(.forward)\ file is syntactially invalid, Exim defers
2737 delivery of all messages to that user, which sometimes include the
2738 user's own test messages. Can it be told to ignore the \(.forward)\ file
2739 and/or inform the user of the error?
2740
2741A0413: Setting \skip_syntax_errors\ on the redirect router causes syntax
2742 errors to be skipped. When dealing with users' \(.forward)\ files it is best
2743 to combine this with a setting of \syntax_errors_to\ in order to send
2744 a message about the error to the user. However, to avoid an infinite
2745 cascade of messages, you have to be able to send to an address that
2746 bypasses \(.forward)\ file processing. This can be done by including a
2747 router like this one
2748
2749==> real_localuser:
2750 driver = accept
2751 check_local_user
2752 transport = local_delivery
90af77f4 2753 local_part_prefix = real-
495ae4b0
PH
2754
2755 before the \%redirect%\ router that handles \(.forward)\ files. This will
2756 do an ordinary local delivery without \(.forward)\ processing, if the
2757 local part is prefixed by \"real-"\. You can then set something like
2758 the following options on the \%redirect%\ router:
2759
2760==> skip_syntax_errors
2761 syntax_errors_to = real-$local_part@$domain
2762 syntax_errors_text = "\
2763 This is an automatically generated message. An error has been \
2764 found\nin your .forward file. Details of the error are reported \
2765 below. While\nthis error persists, messages addressed to you will \
2766 get delivered into\nyour normal mailbox and you will receive a \
2767 copy of this message for\neach one."
2768
2769 A final tidying setting to go with this is a rewriting rule that changes
2770 \"real-username"\ into just \"username"\ in the headers of the message:
2771
2772==> \N^real-([^@]+)@your\.dom\.ain$\N $1@your.dom.ain h
2773
2774 This means that users won't ever see the \"real-"\ prefix, unless they
2775 look at the ::Envelope-To:: header.
2776
2777
2778Q0414: I have set \caseful_local_part\ on the routers that handle my local
2779 domain because my users have upper case letters in their login names,
2780 but incoming mail now has to use the correct case. Can I relax this
2781 somehow?
2782
2783A0414: If you really have to live with caseful user names but want incoming
2784 local parts to be caseless, then you have to maintain a file, indexed by
2785 the lower case forms, that gives the correct case for each login, like
2786 this:
2787
2788==> admin: Admin
2789 steven: Steven
2790 mcdonald: McDonald
2791 lamanch: LaManche
2792 ...
2793
2794 and at the start of the routers that handle your local domain, put one
2795 like this:
2796
2797==> set_case_router:
2798 driver = redirect
2799 data = ${lookup{${lc:$local_part}}lsearch{/the/file}}
2800 qualify_preserve_domain
2801
2802 For efficiency, you should also set the \redirect_router\ option to cause
2803 processing of the changed address to begin at the next router. If you
2804 are otherwise using the default configuration, the setting would be
2805
2806==> redirect_router = system_aliases
2807
2808 If there are lots of users, then a DBM or cdb file would be more
2809 efficient than a linear search. If you are handling several domains,
2810 you will have to extend this configuration to cope appropriately.
2811
2812
2813Q0415: Can I use my existing alias files and forward files as well as procmail
2814 and effectively drop in Exim in place of Sendmail ?
2815
2816A0415: Yes, as long as your alias and forward files don't assume that pipes are
2817 going to run under a shell. If they do, you either have to change them,
2818 or configure Exim to use a shell (which it doesn't by default).
2819
2820
2821Q0416: What is quickest way to set up Exim so any message sent to a
2822 non-existing user would bounce back with a different message, based
2823 on the name of non-existing user?
2824
2825A0416: Place this router last, so that it catches any local addresses that
2826 are not otherwise handled:
2827
2828==> non_exist:
2829 driver = accept
2830 transport = non_exist_reply
2831 no_verify
2832
2833 Then add the following transport to the transports section:
2834
2835==> non_exist_reply:
2836 driver = autoreply
2837 user = exim
2838 to = $sender_address
2839 subject = User does not exist
2840 text = You sent mail to $local_part. That's not a valid user here. \
2841 The subject was: $subject.
2842
2843 If you want to pick up a message from a file, you can use the \file\
2844 option (use \file_expand\ if you want its contents expanded).
2845
2846
2847Q0417: What do I need to do to make Exim handle \(/usr/ucb/vacation)\ processing
2848 automatically, so that people could just create a \(.vacation.msg)\ file in
2849 their home directory and not have to edit their \(.forward)\ file?
2850
2851A0417: Add a new router like this, immediately before the normal \%localuser%\
2852 router:
2853
2854==> vacation:
2855 driver = accept
2856 check_local_user
2857 require_files = $home/.vacation.msg
2858 transport = vacation_transport
2859 unseen
2860
2861 and a matching new transport like this:
2862
2863==> vacation_transport:
2864 driver = pipe
2865 command = /usr/ucb/vacation $local_part
2866
2867 However, some versions of \(/usr/ucb/vacation)\ do not work properly unless
2868 the DBM file(s) it uses are created in advance - it won't create them
2869 itself. You also need a way of removing them when the vacation is over.
2870
2871 Another possibility is to use a fixed filter file which is run whenever
2872 \(.vacation.msg)\ exists, for example:
2873
2874==> vacation:
2875 driver = redirect
2876 check_local_user
2877 require_files = $home/.vacation.msg
2878 file = /some/central/filter
2879 allow_filter
2880
2881 The filter file should use the \"if personal"\ check before sending mail,
2882 to avoid generating automatic responses to mailing lists. If sending a
2883 message is all that it does, this doesn't count as a ``significant''
2884 delivery, so the original message goes on to be delivered as normal.
2885
2886 Yet another possibility is to make use of Exim's \%autoreply%\ transport,
2887 and not use \(/usr/ucb/vacation)\ at all.
2888
2889
2890Q0418: I want to use a default entry in my alias file to handle unknown local
2891 parts, but it picks up the local parts that the aliases generate. For
2892 example, if the alias file is
2893
2894==> luke.skywalker: luke
2895 ls: luke
2896 *: postmaster
2897
2898 then messages addressed to \/luke.skywalker/\ end up at \/postmaster/\.
2899
2900A0418: The default mechanism works best with virtual domains, where the
2901 generated address is not in the same domain. If you just want to pick up
2902 all unknown local parts and send them to postmaster, an easier way to do
2903 it is to put this as your last router:
2904
2905==> unknown:
2906 driver = redirect
2907 data = postmaster
2908 no_verify
2909
2910 Another possibility is to put the redirect router for these aliases
2911 after all the other routers, so that local parts which are user names
2912 get picked off first. You will need to have two aliasing routers if
2913 there are some local parts (e.g. \/root/\) which are login names, but which
2914 you want to handle as aliases.
2915
2916
2917Q0419: I have some obsolete domains which people have been warned not to use
2918 any more. How can I arrange to delete any mail that is sent to them?
2919
2920A0419: To reject them at SMTP time, with a customized error message, place
2921 statments like this in the ACL:
2922
2923==> deny message = The domain $domain is obsolete
2924 domains = lsearch;/etc/exim/obsolete.domains
2925
2926 For messages that don't arrive over SMTP, you can use a router like
2927 this to bounce them:
2928
2929==> obsolete:
2930 driver = redirect
2931 domains = lsearch;/etc/exim/obsolete.domains
2932 allow_fail
2933 data = :fail: the domain $domain is obsolete
2934
2935 If you just want to throw away mail to those domains, accept them at
2936 SMTP time, and use a router like this:
2937
2938==> obsolete:
2939 domains = lsearch;/etc/exim/obsolete.domains
2940 data = :blackhole:
2941
2942
2943Q0420: How can I arrange that mail addressed to \(anything@something.mydomain.com)\
2944 gets delivered to \(something@mydomain.com)\?
2945
2946A0420: Set up a router like this:
2947
2948==> user_from_domain:
2949 driver = redirect
2950 data = ${if match{$domain}{\N^(.+)\.mydomain\.com$\N}\
2951 {$1@mydomain.com}}
2952
2953
2954Q0421: I can't get a regular expression to work in a \local_parts\ option on
2955 one of my routers.
2956
2957A0421: Have you remembered to protect any backslash and dollar characters in
2958 your regex from unwanted expansion? The easiest way is to use the
2959 \"@\N"\ facility, like this:
2960
2961==> local_parts = \N^0740\d{6}\N
2962
2963
2964Q0422: How can I arrange for all addresses in a group of domains \(*.example.com)\
2965 to share the same alias file? I have a number of such groups.
2966
2967A0422: For a single group you could just hard wire the file name into a router
2968 that had
2969
2970==> domains = *.example.com
2971
2972 set, to restrict it to the relevant domains. For a number of such groups
2973 you can create a file containing the domains, like this:
2974
2975==> *.example1.com example1.com
2976 *.example2.com example2.com
2977 ...
2978
2979 Then create a router like this
2980
2981==> domain_aliases:
2982 driver = redirect
2983 domains = partial-lsearch;/that/file
2984 data = ${lookup{$local_part}lsearch*{/etc/aliases.d/$domain_data}}
2985
2986 The variable \$domain_data$\ contains the data that was looked up when the
2987 \domains\ option was matched, i.e. \"example1.com"\, \"example2.com"\, etc.
2988 in this case.
2989
2990
2991Q0423: Some of our users have no home directories; the field in the password
2992 file contains \(/no/home/dir)\. This causes the error \*failed to stat
2993 /no/home/dir (No such file or directory)*\ when Exim tries to look for a
2994 \(.forward file)\, and the delivery is deferred.
2995
2996A0423: There are two issues involved here:
2997
2998 (1) With the default configuration, you are asking Exim to check for a
2999 \(.forward)\ file in the user's home directory. If no file is found,
3000 Exim tries to \^^stat()^^\ the home directory. This is so that it will
3001 notice a missing NFS home directory, and not treat it as if the
3002 \(.forward)\ file did not exist. This \^^stat()^^\ is failing when the
3003 home directory really doesn't exist. You should arrange for the
3004 \%userforward%\ router not to run for these special users, by adding
3005 this line:
3006
3007==> condition = ${if eq {$home}{/no/home/dir}{no}{yes}}
3008
3009 (2) If you use \check_local_user\ on another router to route to a local
3010 transport (again, this is what is in the default configuration), you
3011 will also have to specify a current directory for the transport, because
3012 by default it makes the home directory current. This is easily done by
3013 adding
3014
3015==> current_directory = /
3016
3017 to the transport or
3018
3019==> transport_current_directory = /
3020
3021 to the router. Or you can add \home_directory\ to the transport, because
3022 the current directory defaults to the home directory.
3023
3024
3025Q0424: How can I disable Exim's de-duplication features? I want it to do two
3026 deliveries if two different aliases expand to the same address.
3027
3028A0424: This is not possible. Duplication has other ramifications other than
3029 just (in)convenience. Consider:
3030
3031 . Message is addressed to A and to B.
3032
3033 . Both A and B are aliased to C.
3034
3035 . Without de-duplication, two deliveries to C are scheduled.
3036
3037 . One delivery happens, Exim records that it has delivered the message
3038 to C.
3039
3040 . The next delivery fails (C's mailbox is over quota, say).
3041
3042 Next time round, Exim wants to know if it has already delivered to C or
3043 not, before scheduling a new delivery. Has it? Obviously, if duplicate
3044 deliveries are supported, it has to remember not only that it has
3045 delivered to C but also the ``history'' of how that delivery happened - in
3046 effect an ancestry list back to the original envelope address. This it
3047 does not do, and changing it to work in that way would be a lot of work
3048 and a big upheaval.
3049
3050 The best way to get duplicate deliveries if you want them is not to use
3051 aliases, but to route the addresses directly to a transport, e.g.
3052
3053==> duplicates:
3054 driver = accept
3055 local_parts = lsearch;/etc/list/of/special/local/parts
3056 transport = local_delivery
3057 user = exim
3058
3059
3060Q0425: My users' mailboxes are distributed between several servers according to
3061 the first letter of the user name. All the servers receive incoming mail
3062 at random. I would like to have the same configuration file for all the
3063 servers, which does local delivery for the mailboxes it holds, and sends
3064 other addresses to the correct other server. Is this possible?
3065
3066A0425: It is easiest if you arrange for all the users to have password entries
3067 on all the servers. This means that non-existent users can be detected
3068 at the first server they reach. Set up a file containing a mapping from
3069 the first letter of the user names to the servers where their mailboxes
3070 are held. For example:
3071
3072==> a: server1
3073 b: server1
3074 c: server2
3075 ...
3076
3077 Before the normal \%localuser%\ router, place the following router:
3078
3079==> mailbox_host:
3080 driver = manualroute
3081 check_local_user
3082 transport = remote_smtp
3083 route_list = * ${lookup{${substr_0_1:$local_part}}lsearch{/etc/mapfile}}
3084 self = pass
3085
3086 This router checks for a local account, then looks up the host from the
3087 first character of the local part. If the host is not the local host,
3088 the address is routed to the \%remote_smtp%\ transport, and sent to the
3089 correct host. If the host is the local host, the \self\ option causes
3090 the router to pass the address to the next router, which does a local
3091 delivery.
3092
3093 The router is skipped for local parts that are not the names of local
3094 users, and so these addresses fail.
3095
3096
3097Q0426: One of the things I want to set up is for \(anything@onedomain)\ to forward
3098 to \(anything@anotherdomain)\. I tried adding \($local_part@anotherdomain)\ to
3099 my aliases but it did not expand - it sent it to that literal address.
3100
3101A0426: If you want to do it that way, you can use the \"expand"\ operator on
3102 the lookup used in the data option of the redirect router. For example:
3103
3104==> data = ${expand:${lookup{$local_part}lsearch*{/etc/aliases}}}
3105
3106 Another approach is to use a router like this:
3107
3108==> forwarddomain:
3109 driver = redirect
3110 domains = onedomain
3111 data = $local_part@anotherdomain
3112
3113 The value of \data\ can, of course, be more complicated, involving
3114 lookups etc. if you have lots of different cases.
3115
3116
3117Q0427: How can I have an address looked up in two different alias files, and
3118 delivered to all the addresses that are found?
3119
3120A0427: Use a router like this:
3121
3122==> multi_aliases:
3123 driver = redirect
3124 data = ${lookup{$local_part}lsearch{/etc/aliases1}\
3125 {$value${lookup{$local_part}lsearch{/etc/aliases2}{,$value}}}\
3126 {${lookup{$local_part}lsearch{/etc/aliases2}{$value}fail}}}\
3127
3128 If the first lookup succeeds, the result is its data, followed by the
3129 data from the second lookup, if any, separated by a comma. If the first
3130 lookup fails, the result is the data from the third lookup (which also
3131 looks in the second file), but if this also fails, the entire expansion
3132 is forced to fail, thereby causing the router to decline.
3133
3134 Another approach is to use two routers, with the first re-generating the
3135 original local part when it succeeds. This won't get processed by the
3136 same router again. For example:
3137
3138==> multi_aliases1:
3139 driver = redirect
3140 data = ${lookup{$local_part}lsearch{/etc/aliases1}{$value,$local_part}}
3141
3142==> multi_aliases2:
3143 data = ${lookup{$local_part}lsearch{/etc/aliases2}}
3144
3145 This scales more easily to three or more alias files.
3146
3147
3148Q0428: I've converted from Sendmail, and I notice that Exim doesn't make use
3149 of the \"owner-"\ entries in my alias file to change the sender address in
3150 outgoing messages to a mailing list.
3151
3152A0428: If you have an alias file with entries like this:
3153
3154==> somelist: a@b, c@d, ...
3155 owner-somelist: postmaster
3156
3157 Sendmail assumes that the second entry specifies a new sender address
3158 for the first. Exim does not make this assumption. However, you can make
3159 it take the same action, by adding
3160
3161==> errors_to = owner-$local_part@whatever.domain
3162
3163 to the configuration for your aliasing router. This is fail-safe,
3164 because Exim verifies a new sender address before using it. Thus, the
3165 change of sender address occurs only when the owner entry exists.
3166
3167
3168Q0429: I would like to deliver mail addressed to a given domain to local
3169 mailboxes, but also to generate messages to the envelope senders.
3170
3171A0429: You can do this with an ``unseen'' router and an \%autoreply%\ transport,
3172 along the following lines:
3173
3174==> # Router
3175 auto_warning_r:
3176 driver = accept
3177 check_local_user
3178 domains = <domains you want to do this for>
3179 condition = ${if eq{$sender_address}{}{no}{yes}}
3180 transport = warning_t
3181 no_verify
3182 unseen
3183
3184 Place this router immediately before the normal \%localuser%\ router. The
3185 \unseen\ option means that the address is still passed on to the next
3186 router. The transport is configured like this:
3187
3188==> # Transport
3189 warning_t:
3190 driver = autoreply
3191 file = /usr/local/mail/warning.txt
3192 file_expand
3193 from = postmaster@your.domain
3194 to = $sender_address
3195 user = exim
3196 subject = Re: Your mail to $local_part@$domain
3197
3198 Note the use of the \condition\ option to avoid attempting to send a
3199 message when there is no sender (that is, when the incoming message is a
3200 bounce message). You can of course extend this to include other
3201 conditions. If you want to log the sending of messages, you can add
3202
3203==> log = /some/file
3204
3205 to the transport and also make use of the \once\ option if you want to
3206 send only one message to each sender.
3207
3208
3209Q0430: Whenever Exim tries to route a local address, it gives a permission
3210 denied error for the \(.forward)\ file, like this:
3211
3212==> 1998-08-10 16:55:32 0z5y2W-0000B8-00 == xxxx@yyy.zzz <xxxx@yyy.zz>
3213 D=userforward defer (-1): failed to open /home/xxxx/.forward
3214 (userforward router): Permission denied (euid=1234 egid=101)
3215
3216A0430: Have you remembered to make Exim setuid \/root/\?
3217
3218
3219Q0431: How do I configure Exim to allow arbitrary extensions in local parts, of
3220 the form \/+extension/\?
3221
3222A0431: Add this pre-condition to the relevant router:
3223
3224==> local_part_suffix = +*
3225
3226 If you want the extensions to be optional, also add the option
3227
3228==> local_part_suffix_optional
3229
3230 When the router runs, \$local_part$\ contains the local part with the
3231 extension removed, and the extension (if any) is in \$local_part_suffix$\.
3232 If you have set \check_local_user\, the test is carried out after the
3233 extension is removed.
3234
3235
3236Q0432: I use NIS for my user data. How can I stop Exim rejecting mail when my
3237 NIS servers are being restarted?
3238
3239A0432: Exim doesn't know that you are using NIS; it just calls the \^^getpwnam()^^\
3240 function, which is routed by nsswitch. Unfortunately, \^^getpwnam()^^\
3241 was never designed to be routed through NIS, and it returns NULL if the
3242 entry is not found or if the connection to the NIS server fails. This
3243 means that Exim cannot tell the difference between ``no such user'' and
3244 ``NIS is down''.
3245
3246 Crutches to help with this problem are \finduser_retries\ in Exim, and
3247 \^nscd^\ on the Unix side, but they are not perfect, and mail can still
3248 be lost. However, Nico Erfurth pointed out that you can create a router
3249 for Exim that tests for the availability of NIS, and force a defer if
3250 NIS is not running:
3251
3252==> check_nis:
3253 driver = redirect
3254 data = ${lookup {$local_part} nis {passwd}{}}
3255
3256 This should be placed before any router that makes any use of NIS,
3257 typically at the start of your local routers. How does it work? If
3258 your NIS server is reachable, the lookup will take place, and whether it
8e26e4bf 3259 succeeds or fails, the result is an empty string. This causes the
495ae4b0
PH
3260 router to decline, and the address is passed to the following routers.
3261 If your NIS server is down, the lookup defers, and this causes the
3262 router to defer. A verification of an incoming address gets a temporary
3263 rejection, and a delivery is deferred till later.
3264
3265
8e26e4bf
PH
3266Q0433: How can I arrange for a single address to be processed by both
3267 \%redirect%\ and \%accept%\?
495ae4b0
PH
3268
3269A0433: Check out the \unseen\ option.
3270
3271
3272Q0434: How can I redirect all local parts that are not in my system aliases to
3273 a single address? I tried using an asterisk in the system alias file
8e26e4bf 3274 with an \"lsearch*"\ lookup, but that sent all messages to the
495ae4b0
PH
3275 default address.
3276
3277A0434: If your alias file generates addresses in the local domain, they are
3278 also processed as a potential aliases. For example, suppose this is your
3279 alias file:
3280
3281==> caesar: jc
3282 anthony: ma
3283 *: brutus
3284
3285 The local part \/caesar/\ is aliased to \/jc/\, but that address is then
3286 reprocessed by the routers. As the address is in the local domain, the
3287 alias file is again consulted, and this time the default matches. In
3288 fact after the second aliasing, \/brutus/\ is also processed again from
3289 the start, and is aliased to itself. However, this happens only once,
3290 because the next time, Exim notices that the aliasing router has already
3291 processed \/brutus/\, so the router is skipped in order to avoid
3292 looping.
3293
3294 There are several ways of solving this problem; which one you use
3295 depends on your aliasing data.
3296
3297 (1) If the result of aliasing is always a local user name, that is,
3298 aliasing never generates another alias, you can use the
3299 \redirect_router\ option on the router to specify that processing
3300 the generated addresses must start at the next router. For example:
3301
3302==> redirect_router = userforward
3303
3304 assuming that the next router is called \%userforward%\. This
3305 ensures that there is at most one pass through the aliasing router.
3306
3307 (2) If you cannot rely on aliases generating non-aliases, it is often
3308 easier not to use a default alias, but instead to place a router
3309 such as the one below after all the other local routers (for the
3310 relevant domains):
3311
3312==> catch_unknown:
3313 driver = redirect
3314 domains = ...
3315 data = brutus@$domain
3316
3317 Note that the default aliasing technique works more successfully for
3318 virtual domains (see Q0401) because the generated address for the
3319 default is not usually in the same virtual domain as the incoming
3320 address.
3321
3322
3323Q0435: My alias file contains fully qualified addresses as keys, and some
3324 wildcard domains in the form @foo.bar. Can Exim handle these?
3325
3326A0435: You can handle fully qualified addresses with this router:
3327
3328==> qualified_aliases:
3329 driver = redirect
3330 data = ${lookup{$local_part@$domain}lsearch{/etc/aliases}}
3331
3332 (Add any other options you need for the \%redirect%\ router.) Place this
3333 router either before or after the default aliases router that looks up
3334 the local part only. (Or, if you have no unqualified aliases, replace
3335 the default router.)
3336
3337 To handle wildcards in the form @foo.bar you will need yet another
3338 router. (Wildcards of the form *@foo.bar can be handled by an lsearch*@
3339 lookup.) Something like this:
3340
3341==> wildcard_aliases:
3342 driver = redirect
3343 data = ${lookup{@$domain}lsearch{/etc/aliases}}
3344
3345 Place this after the routers that handle the more specific aliases.
3346
3347
3348
33495. FILTERING
3350
3351Q0501: My filter isn't working. How can I test it?
3352
3353A0501: Use the \-bf-\ option (\-bF-\ for a system filter) to test the basic operation
3354 of your filter. You can request debugging information for filtering only
3355 by adding \"-d-all+filter"\ to the command.
3356
3357
3358Q0502: What I really need is the ability to obtain the result of a pipe
3359 command so that I can filter externally and redirect internally. Is
3360 this possible?
3361
3362A0502: The result of a pipe command is not available to a filter, because Exim
3363 does not run any actual deliveries while filtering. It just sets up
3364 deliveries at this time. They all actually happen later. If you want to
3365 run pipes and examine their results, you need to set up a single
3366 delivery to a delivery agent such as \^procmail^\ which provides this kind
3367 of facility.
3368
3369 An possible alternative is to use the \"${run"\ expansion item to run an
3370 external command while filtering. In this case, you can make use of some
3371 of the results of the command.
3372
3373
3374Q0503: I received a message with a ::Subject:: line that contained a non-printing
3375 character (a carriage return). This messed up my filter file. Is there a
3376 way to get round it?
3377
3378A0503: Instead of \"$h_subject:"\ use \"${escape:$h_subject:}"\
3379
3380
3381Q0504: I want to search for \"$"\ in the subject line, but I can't seem to get
3382 the syntax.
3383
3384A0504: Try one of these:
3385
3386==> if $h_subject: contains \$ then ...
3387 if $h_subject: contains "\\$" then ...
3388
3389
3390Q0505: My problem is that Exim replaces \$local_part$\ with an empty string in the
3391 system filtering. What's wrong or what did I miss?
3392
3393A0505: A message may have many recipients. The system filter is run just once
3394 at the start of a delivery attempt. Consequently, it does not make sense
3395 to set \$local_part$\. Which recipient should it be set to? However, you
3396 can access all the recipients from a system filter via the variable
3397 called \$recipients$\.
3398
3399
3400Q0506: Using \$recipients$\ in a system filter gives me another problem: how can
3401 I do a string lookup if \$recipients$\ is a list of addresses?
3402
3403A0506: Check out the section of the filter specification called \*Testing a list of
3404 addresses*\. If that doesn't help, you may have to resort to calling an
3405 embedded Perl interpreter - but that is expensive.
3406
3407
3408Q0507: What are the main differences between using an Exim filter and using
3409 \^procmail^\?
3410
3411A0507: Exim filters and \^procmail^\ provide different facilities. Exim filters run
3412 at routing time, before any deliveries are done. A filter is like a
3413 ``\(.forward)\ file with conditions''. One of the benefits is de-duplication.
3414 Another is that if you forward, you are forwarding the original message.
3415
3416 However, this does mean that pipes etc. are not run at filtering time,
3417 nor can you change the headers, because the message may have other
3418 recipients and Exim keeps only a single set of headers.
3419
3420 \^procmail^\ runs at delivery time. This is for one recipient only, and so
3421 it can change headers, run pipes and check the results, etc. However, if
3422 it wants to forward, it has to create a new message containing a copy
3423 of the original message.
3424
3425 It's your choice as to which of these you use. You can of course use
3426 both.
3427
3428
3429Q0508: How can I allow the use of relative paths in users' filter files when
3430 the directories concerned are not available from the password data?
3431
3432A0508: You need to be running Exim 4.11 or later. You can then specify a value
3433 for \$home$\ by setting the router_home_directory option on the
3434 \%redirect%\ router.
3435
3436 For earlier releases, there is no way to specify the value of \$home$\
3437 for a \%redirect%\ router; it either comes from the password data as a
3438 result of \check_local_user\, or is unset.
3439
3440
3441Q0509: How can I set up a filter file to detect and block virus attachments?
3442
3443A0509: Exim's filter facilities aren't powerful enough to do much more than
3444 very crude testing. Most people that want virus checking are nowadays
3445 using one of the separate scanning programs such as \^exiscan^\ (see
3446 \?http://duncanthrax.net/exiscan/?\). There is some further information
3447 about scanning with Exim via \?http://www.timj.co.uk/linux/exim.php?\.
3448
3449
3450Q0510: Is it possible to write code for scanning messages in Python?
3451
3452A0510: \^elspy^\ is a layer of glue code that enables you to write Python code
3453 to scan email messages at SMTP time. \^elspy^\ also includes a small
3454 Python library with common mail-scanning tools, including an interface
3455 to SpamAssassin and a simple but effective virus detector. You can
3456 optain \^elspy^\ from \?http://elspy.sourceforge.net/?\.
3457
3458
3459Q0511: Whenever my system filter uses a \mail\ command to send a message, I get
3460 the error \*User 0 set for address_reply transport is on the never_users
3461 list*\. What does this mean?
3462
3463A0511: The system filter runs as \/root/\ in Exim 4, unless you set
3464 \system_filter_user\ to specify otherwise. When you set up a delivery
3465 direct from a system filter (an autoreply is a special kind of
3466 ``delivery'') the transport runs as the same user, unless it has a
3467 \user\ setting of its own. Normally, deliveries are not allowed to run
3468 as \/root/\ as a security precaution; this is implemented by the
8e26e4bf 3469 \never_users\ option (see Q0039).
495ae4b0
PH
3470
3471 The easiest solution is to add this to your configuration:
3472
3473==> system_filter_user = exim
3474
3475 The system filter then runs as \/exim/\ instead of \/root/\.
3476 Alternatively, you can arrange for autoreplies from the system filter to
3477 use a special transport of their own, and set the \user\ option on that
3478 transport.
3479
3480
3481Q0512: I'm trying to reference the ::Envelope-To:: header in my filter, but
3482 \$h_envelope-to:$\ is always empty.
3483
3484A0512: ::Envelope-To:: is added at delivery time, by the transport. Therefore,
3485 the header doesn't exist at filter time. In a user filter, the values
3486 you probably want are in \$original_local_part$\ and
3487 \$original_domain$\. In a system filter, the complete list of all
3488 envelope recipients is in \$recipients$\.
3489
3490
3491Q0513: I want my system filter to freeze all mails greater than 500K in size,
3492 but to exclude those to a specific domain. However, I don't seem to be
3493 able to use \$domain$\ in a system filter.
3494
3495A0513: You cannot do this in a system filter, because a single message may have
3496 multiple recipients, some in the special domain, and some not. That is
3497 also the reason why \$domain$\ is not set in a system filter.
3498
3499 If you want to take actions on a per-recipient basis, you have to do it
3500 in a router. However, freezing is not appropriate, because freezing
3501 stops all deliveries. You could, however, delay delivery to all but the
3502 special domains by using something like this:
3503
3504==> delay_if_too_big:
3505 driver = redirect
3506 domains = !the.special.domain
3507 condition = ${if >{$message_size}{500K}{yes}{no}}
3508 allow_defer
3509 data = :defer: message too big.
3510
3511 However, there isn't an easy way of ``releasing'' such messages at
3512 present.
3513
3514
3515Q0514: When I try to send to two addresses I get an error in the filter
3516 file \*malformed address: , e@fgh.com may not follow a@bcd.com*\. What
3517 is going on?
3518
3519A0514: Have you got
3520
3521==> deliver "a@bcd.com, e@fgh.com"
3522
3523 in your filter? If so, that is your problem. You should have
3524
3525==> deliver a@bcd.com
3526 deliver e@fgh.com
3527
3528 Each \deliver\ command expects just one address.
3529
3530
3531
35326. DELIVERY
3533
3534Q0601: What does the error \*Neither the xxx router nor the yyy transport set
3535 a uid for local delivery of...*\ mean?
3536
3537A0601: Whenever Exim does a local delivery, it runs a process under a specific
3538 user and group id (uid and gid). For deliveries into mailboxes, and to
3539 pipes and files set up by forwarding, it normally picks up the uid/gid
3540 of the receiving user. However, if an address is directed to a pipe or a
3541 file by some other means, such an entry in the system alias file of the
3542 form
3543
3544==> majordomo: |/local/mail/majordomo ...
3545
3546 then Exim has to be told what uid/gid to use for the delivery. This can
3547 be done either on the routerr that handles the address, or on the
3548 transport that actually does the delivery. If a pipe is going to run a
3549 setuid program, then it doesn't matter what uid Exim starts it out with,
3550 and so the most straightforward thing is to put
3551
3552==> user = exim
3553
3554 on either the router or the transport. A setting on the transport
3555 overrides a setting on the router, so if the same transport is being
3556 used with several routers, you should set the user on it only if you
3557 want the same uid to be used in all cases.
3558
3559 In the default configuration, the transports used for file and pipe
3560 deliveries are the ones called \address_file\ and \address_pipe\. You
3561 can specify different transports by setting, for example,
3562
3563==> pipe_transport = special_pipe_transport
3564
3565 on the \%system_aliases%\ router. Then you can set up \%special_pipe_transport%\
3566
3567==> special_pipe_transport:
3568 driver = pipe
3569 user = ????
3570
3571 which will be used only for pipe deliveries from that one router.
3572 What you put for the ???? is up to you, and depends on the particular
3573 circumstances.
3574
3575
3576Q0602: Exim keeps crashing with segmentation errors (signal 11 or 139) during
3577 delivery. This seems to happen when it is about to contact a remote
3578 host or when a delivery is deferred.
3579
3580A0602: This could be a problem with Exim's databases. Try running a delivery
3581 with debugging turned on. If the last line of the debug output is
3582 something like this:
3583
3584==> locked /var/spool/exim/db/retry.lockfile
3585
3586 the crash is happening inside the DBM library. Check that your DBM
3587 library is correctly installed. In particular, if you have installed a
3588 second DBM library onto a system that already had one, check that its
3589 version of \(ndbm.h)\ is being seen first. For example, if the new
3590 version is in \(/usr/local/include)\, check that there isn't another
3591 version in \(/usr/include)\. If you are using Berkeley db, you can set
3592
3593==> USE_DB=yes
3594
3595 in your \(Local/Makefile)\ to avoid using \(ndbm.h)\ altogether. This is
3596 particularly relevant for version 2 (or later) of Berkeley db, because
3597 no \(ndbm.h)\ file is distributed with it. Another thing you can try is
3598 to run
3599
3600==> exim_dumpdb /var/spool/exim retry
3601
3602 to see if it also crashes, or build the \^test_dbfn^\ tool and fiddle
3603 around with it. If both fail, it is most almost certainly a problem with
3604 your DBM library. You could try to update it, or force Exim to use
3605 another library. See the file \(doc/dbm.discuss.txt)\ for hints about
3606 this.
3607
3608
3609Q0603: How can mails that are being routed through routers that do not set
3610 \check_local_user\ be delivered under the uid of the recipient?
3611
3612A0603: Q0601 contains background information on this. If you are using, say, an
3613 alias file to direct messages to specific mailboxes, you can use
3614 the \user\ option on either the router or the transport to set the uid.
3615 What you put in the setting depends on how the required uid is to be
3616 found. It could be looked up in a file or computed somehow from the
3617 local part, for example.
3618
3619
3620Q0604: I want to use MMDF-style mailboxes. How can I get Exim to append the
3621 ctrl-A characters that separate indvidual emails?
3622
3623A0604: Set the \message_suffix\ option in the \%appendfile%\ transport. In fact,
3624 for MMDF mailboxes you need a prefix as well as a suffix to get it
3625 working right, so your transport should contain these settings:
3626
3627==> message_prefix = "\1\1\1\1\n"
3628 message_suffix = "\1\1\1\1\n"
3629
3630 Also, you need to change the \check_string\ and \escape_string\ settings so
3631 that the escaping happens for lines in the message that happen to begin
3632 with the MMDF prefix or suffix string, rather than ``From'' (the default):
3633
3634==> check_string = "\1\1\1\1\n"
3635 escape_string = "\1\1\1\1 \n"
3636
3637 Adding a space to the line is sufficient to prevent it being taken as a
3638 separator.
3639
3640
3641Q0605: If a user's mailbox is over quota, is there a way for me to set it up so
3642 that the mail bounces to the sender and is not stored in the mail queue?
3643
3644A0605: In the retry section of the configuration, put
3645
3646==> *@your.dom.ain quota
3647
3648 That is, provide no retry timings for over quota errors. They will then
3649 bounce immediately. Alternatively, you can set up retries for a short
3650 time only, or use something like this:
3651
3652==> *@your.dom.ain quota_7d
3653 *@your.dom.ain quota F,2h,15m; F,3d,1h
3654
3655 which bounces immediately if the user's mailbox hasn't been read for 7
3656 days, but otherwise tries for up to 3 days after the first quota
3657 failure.
3658
3659
3660Q0606: I'm using tmail to do local deliveries, but when I turned on the
3661 \use_crlf\ option on the \%pipe%\ transport (tmail prefers \"@\r@\n"\
3662 terminations) message bodies started to vanish.
3663
3664A0606: You need to unset the \mesage_prefix\ option, or change it so that its
3665 default \"@\n"\ terminator becomes \"@\r@\n"\. For example, the
3666 transport could be:
3667
3668==> local_delivery_mbx:
f0884f39
PH
3669 driver = pipe
3670 command = /usr/local/bin/tmail $local_part
3671 user = exim
3672 current_directory = /
495ae4b0
PH
3673 use_crlf
3674 message_prefix =
3675
3676 The reason for this is as follows: tmail uses the line terminator on
3677 the first line it sees to determine whether lines are terminated by
3678 \"@\r@\n"\ or \"@\n"\. If the latter, it moans to stderr and changes subsequent
3679 \"@\n"\ terminators to \"@\r@\n"\. The default setting of the \message_prefix\
3680 option is \"From ...@\n"\, and this is unaffected by the \use_crlf\ option.
3681 If you don't change this, tmail sees the first line terminated by
3682 \"@\n"\ and prepends \"@\r"\ to the \"@\n"\ terminator on all subsequent
3683 lines. However, if \use_crlf\ is set, Exim makes all other lines
3684 \"@\r@\n"\ terminated, leading to doubled \"@\r@\r@\n"\ lines and
3685 corrupt mbx mailboxes.
3686
3687
3688Q0607: When I activate ``return receipt'' for example in Netscape Mailbox
3689 sending options, then I get an error message from Exim... something
3690 like \*not supported*\. Can I activate delivery confirmations?
3691
3692A0607: Exim does not support any kind of delivery notification.
3693
3694 (1) You can configure it to recognize headers such as
3695 \Return-receipt-to:\ if you wish.
3696
3697 (2) Some people want MSN (message status notification). Such services
3698 are implemented in MUAs, and don't impact on the MTA at all.
3699
3700 (3) I investigated the RFCs which describe the DSN (delivery status
3701 notification) system. However, I was unable to specify any sensible way
3702 of actually doing anything with the data. There were comments on the
3703 mailing list at the time; many people, including me, conclude that DSN
3704 is in practice unworkable. The killer problem is with forwarding and
3705 aliasing. Do you propagate the DSN data with the generated addresses?
3706 Do you send back a ``reached end of the DSN world'' or ``expanded'' message?
3707 Do you do this differently for different kinds of aliasing/forwarding?
3708 For a user who has a \(.forward)\ file with a single address in, this
3709 might seem easy - just propagate the data. But what if there are several
3710 forwardings? If you propagate the DSN data, the sender may get back
3711 several DSN messages - and should the sender really know about the
3712 detail of the receiver's forwarding arrangements? There isn't really
3713 any way to distinguish between a \(.forward)\ file that is forwarding
3714 and one that is a mini mailing list. And so on, and so on. There are so
3715 many questions that don't have obvious answers.
3716
3717
3718Q0608: What does the message \*retry time not reached [for any host]*\ on the log
3719 mean? Why won't Exim try to deliver the message?
3720
3721A0608: That is not an error. It means exactly what it says. A previous attempt
3722 to deliver to that address failed with a temporary error, and Exim
3723 computed the earliest time at which to try again. This can apply to
3724 local as well as to remote deliveries. For remote deliveries, each host
3725 (if there are several) has its own retry time.
3726
3727 If you are running on a dial-up host, the rest of this answer probably
3728 does not apply to you. Go and read Q1404 instead. If your host is
3729 permanently online, read on...
3730
3731 Some MTAs have a retrying schedule for each message. Exim does not work
3732 like this. Retry timing is normally host-based for remote deliveries and
3733 address-based for local deliveries. (There are some exceptions for certain
3734 kinds of remote failure - see \*Errors in outgoing SMTP*\ in the manual.)
3735
3736 If a new message arrives for a failing address and the retry time has
3737 not yet arrived, Exim will log \*retry time not reached*\ and leave the
3738 message on the queue, without attempting delivery. Similarly, if a queue
3739 runner notices the message before the time to retry has arrived, it
3740 writes the same log entry. When the retry time has past, Exim attempts
3741 delivery at the next queue run. If you want to know when that will be,
3742 run the exinext utility on the address, for example:
3743
3744==> exinext user@some.domain
3745
3746 You can suppress these messages on the log by including \"-retry_defer"\
3747 in the setting of \log_selector\. You can force a delivery attempt on a
3748 specific message (overriding the retry time) by means of the -M option:
3749
3750==> exim -M 10hCET-0000Bf-00
3751
3752 If you want to do this for the entire queue, use the \-qf-\ option.
3753
3754
3755Q0609: Exim seems to be sending the same message twice, according to the log,
3756 although there is a difference in capitalization of the local part of
3757 the address.
3758
3759A0609: That is correct. The RFCs are explicit in stating that capitalization
3760 matters for local parts. For remote domains, Exim is not entitled to
3761 assume case independence of local parts. I know, it is utterly silly,
3762 and it causes a lot of grief, but that's what the rules say. Here is a
3763 quote from RFC 2821:
3764
3765 ... a command verb, an argument value other than a mailbox local-part,
3766 and free form text MAY be encoded in upper case, lower case, or any
3767 mixture of upper and lower case with no impact on its meaning. This
3768 is NOT true of a mailbox local-part. The local-part of a mailbox
3769 MUST BE treated as case sensitive. Therefore, SMTP implementations
3770 MUST take care to preserve the case of mailbox local-parts. Mailbox
3771 domains are not case sensitive. In particular, for some hosts the
3772 user "smith" is different from the user "Smith". However, exploiting
3773 the case sensitivity of mailbox local-parts impedes interoperability
3774 and is discouraged.
3775
3776
3777Q0610: How can I force the next retry time for a host to be now?
3778
3779A0610: You can change the retry time with the \^exim_fixdb^\ utility, but its
3780 interface is very clumsy. If you have a message for the host on the
3781 queue, the simplest thing to do is to force a delivery with the \-M-\
3782 command line option. If delivery succeeds, the retry data will get
3783 cleared. If the host is past the cutoff time, so that messages are
3784 bouncing immediately without trying a delivery, you can use \-odq-\ to
3785 put a message on the queue without a delivery attempt, and then use
3786 \-M-\ on it.
3787
3788
3789Q0611: I set up \"|/bin/grep Subject|/usr/bin/smbclient -M <netbiosname>"\ as an
3790 alias but it doesn't work.
3791
3792A0611: That is a shell command line. Exim does not run pipe commands under a
3793 shell by default (for added security - and it saves a process). You
3794 need something like
3795
3796==> "|/bin/sh -c '/bin/grep Subject|/usr/bin/smbclient -M <netbiosname>'"
3797
3798
3799Q0612: Why does the \%pipe%\ transport add a line starting with \">From"\ to
3800 messages?
3801
3802A0612: Actually, it adds a line starting with \"From"\ followed by a space.
3803 This is commonly referred to as the \"From_"\ line, to emphasize the
3804 fact that \"From"\ is followed by a space and not a colon. This is a
3805 pseudo-header line that contains the envelope sender address and the
3806 time of delivery. It originated as a separator line in Berkeley format
3807 mailboxes, but is also used in other contexts. (And yes, it is often
3808 confused with the ::From:: header line, and this causes a lot of grief.
3809 The use of \"From_"\ was one of the really bad email design decisions.)
3810
3811 Exim's \%pipe%\ transport adds this pseudo-header line by default
3812 because \(/usr/ucb/vacation)\ needs it, and that is one of the the most
3813 common uses of piping. The \^procmail^\ local delivery agent also makes
3814 use of the \"From_"\ line. If you do not want it, change the setting of
3815 \message_prefix\ on the \%pipe%\ transport. For example, to remove the
3816 line altogether, use
3817
3818==> message_prefix =
3819
3820 If you are not piping to \(/usr/ucb/vacation)\ or \^procmail^\, it is
3821 likely that you do not need a \"From_"\ line, and indeed it may cause
3822 problems if it is present.
3823
3824 One user reported that this line gave trouble when a pipe was used to
3825 send messages to Courier's \^deliverquota^\ program. The line was
3826 retained with the message, and caused problems for MS Exchange 2000 when
3827 retrieving messages with its built-in POP collector. Specifically, it
3828 caused Exchange to not be able to recognise message attachments.
3829
3830
3831Q0613: I have set \fallback_hosts\ on my \%smtp%\ transport, but after the error
3832 \*sem@chat.ru cannot be resolved at this time*\ Exim isn't using them.
3833
3834A0613: \fallback_hosts\ works only if an attempt at delivery to the original
3835 host(s) fails. In this case, Exim couldn't even resolve the domain
3836 \(chat.ru)\ to discover what the original hosts were, so it never got as far
3837 as the transport. However, see Q0315 for a possible solution.
3838
3839
3840Q0614: After the holidays my ISP has always hundreds of e-mails waiting for me.
3841 These are forced down Exim's throat in one go. Exim spawns a lot of
3842 kids, but is there some limit to the number of processes it creates?
3843
3844A0614: Unless you have changed \smtp_accept_queue_per_connection\ it should
3845 spawn only that many processes per connection (default 10). Your ISP
3846 may be making many connections, of course. That is limited by
3847 \smtp_accept_max\.
3848
3849
3850Q0615: When a message in the queue got to 12h old, Exim wrote \*retry timeout
3851 exceeded*\ and removed all messages in the queue to this host - even
3852 recent messages. How I can avoid this behaviour? I only want to remove
3853 messages that have exceeded the maximum retry time.
3854
3855A0615: Exim's retrying is host-based rather than message-based. The philosophy
3856 is that if a host has been down for a very long time, there is no point
3857 in keeping messages hanging around. However, you might like to check
3858 out \delay_after_cutoff\ in the \%smtp%\ transport. It doesn't do what you
3859 want, but it might help.
3860
3861
3862Q0616: Can Exim add a ::Content-Length:: header to messages it delivers?
3863
3864A0616: You could include something like
3865
3866==> headers_remove = "content-length"
3867 headers_add = "Content-Length: $message_body_size"
3868
3869 to the \%appendfile%\ transport. However, the use of ::Content-Length:: can
3870 cause several problems, and is not recommended unless you really know
3871 what you are doing. There is a discussion of the problems in
3872 \?http://home.netscape.com/eng/mozilla/2.0/relnotes/demo/content-length.html?\.
3873
3874
3875Q0617: Exim seems to be trying to deliver a message every 10 minutes, though
3876 the retry rules specify longer times after a while, because it is
3877 writing a log entry every time, like this:
3878
3879==> 1999-08-26 14:51:19 11IVsE-000MuP-00 == example@example.com T=smtp defer
3880 (-34): some host address lookups failed and retry time not reached for
3881 other hosts or connection limit reached
3882
3883A0617: It is looking at the message every 10 minutes, but it isn't actually
3884 trying to deliver. It's looking up \(example.com)\ in the DNS and finding
3885 this information:
3886
3887==> example.com. MX 10 example-com.isp.example.com.
3888 example.com. MX 0 mail.example.com.
3889 mail.example.com. A 202.77.183.45
3890 A lookup for example-com.isp.example.com. yielded NXDOMAIN
3891
3892 The last line means that there is no address (A) record in the DNS for
3893 \(example-com.isp.example.com)\. That accounts for \*some host address
3894 lookups failed*\, but the retry time for \(mail.example.com)\ hasn't been
3895 reached, which accounts for \*retry time not reached for other hosts*\.
3896
3897
3898Q0618: I am trying to set exim up to have a automatic failover if it sees that
3899 the system that it is sending all mail to is down.
3900
3901A0618: Add to the \%remote_smtp%\ transport the following:
3902
3903==> fallback_hosts = failover.server.name(s)
3904
3905 If there are several names, they must be separated by colons.
3906
3907
3908Q0619: I can't get Exim to deliver over NFS. I get the error \*fcntl() failed:
3909 No locks available*\, though the lock daemon is running on the NFS server
3910 and other hosts are able to access it.
3911
3912A0619: Check that you have \(lockd)\ running on the NFS client. This is not