Log tcp errors (#188)

diff --git a/tcp.go b/tcp.go
index 3a1ac2fdcaa65a42622e86a59c7ca83fd2c67252..d823f42ba053f1ee81977fc8a320c87062ddbc9d 100644 (file)
--- a/tcp.go
+++ b/tcp.go
@@ -32,11 +32,13 @@ func dialTCP(target string, module Module, registry *prometheus.Registry) (net.C
 
        targetAddress, port, err := net.SplitHostPort(target)
        if err != nil {
+               log.Errorf("Error splitting target address and port: %v", err)
                return nil, err
        }
 
        ip, err := chooseProtocol(module.TCP.PreferredIPProtocol, targetAddress, registry)
        if err != nil {
+               log.Errorf("Error choosing protocol: %v", err)
                return nil, err
        }
 
@@ -52,6 +54,7 @@ func dialTCP(target string, module Module, registry *prometheus.Registry) (net.C
        }
        tlsConfig, err := config.NewTLSConfig(&module.TCP.TLSConfig)
        if err != nil {
+               log.Errorf("Error creating TLS configuration: %v", err)
                return nil, err
        }
        return tls.DialWithDialer(dialer, dialProtocol, dialTarget, tlsConfig)
@@ -66,6 +69,7 @@ func probeTCP(target string, module Module, registry *prometheus.Registry) bool
        deadline := time.Now().Add(module.Timeout)
        conn, err := dialTCP(target, module, registry)
        if err != nil {
+               log.Errorf("Error dialing TCP: %v", err)
                return false
        }
        defer conn.Close()
@@ -74,6 +78,7 @@ func probeTCP(target string, module Module, registry *prometheus.Registry) bool
        // If a deadline cannot be set, better fail the probe by returning an error
        // now rather than blocking forever.
        if err := conn.SetDeadline(deadline); err != nil {
+               log.Errorf("Error setting deadline: %v", err)
                return false
        }
        if module.TCP.TLS {