[Dovecot] Dovecot not accepting connections

[Jim]

On Mar 26, 2009, at 6:01 PM, Timo Sirainen wrote:

> On Mar 25, 2009, at 10:47 PM, Jim wrote:
>
>> Nothing unusual in the logs, if it works or not, I'll just see this  
>> at startup:
>>
>> Mar 25 21:34:48 mail-web-server dovecot[664]: dovecot v1.1.13  
>> starting up (core dumps disabled)
>> Mar 25 21:34:48 mail-web-server dovecot[664]: auth-worker(default):  
>> mysql: Connected to localhost (postfix)
>>
>> If debug is on and connections aren't being accepted, I never see  
>> anything in the logs.
>
> And what does "not accepting connections" mean? Does the TCP  
> handshake finish? For example if you do:
>
> telnet localhost 143
>
> Does it
>
> a) Hang after "Trying 127.0.0.1..."
> b) Hang after "Escape character is '^]'."
> c) Say connect to address 127.0.0.1: Connection refused

mail-web-server:~ wright$ telnet localhost 143
Trying ::1...
telnet: connect to address ::1: Connection refused
Trying fe80::1...
telnet: connect to address fe80::1: Connection refused
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
* OK Dovecot ready.

mail-web-server:~ wright$ telnet localhost 110
Trying ::1...
telnet: connect to address ::1: Connection refused
Trying fe80::1...
telnet: connect to address fe80::1: Connection refused
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
+OK Dovecot ready.

My various attempts to quit both of these sessions showed the  
following in the log:

Mar 28 20:48:03 mail-web-server dovecot[227]: imap-login:  
Disconnected: Too many invalid commands (no auth attempts):  
rip=127.0.0.1, lip=127.0.0.1, secured
Mar 28 20:48:26 mail-web-server dovecot[227]: pop3-login: Aborted  
login (no auth attempts): rip=127.0.0.1, lip=127.0.0.1, secured

The above does seem like Dovecot is running properly.  But when  
checking mail via my mail client (OS X, Mail.app, POP account), the  
connection attempts for about 30 seconds, then aborts.  Likewise,  
trying an IMAP login via webmail (RoundCube) fails after about 15  
seconds.  Nothing in the log from either of these attempts.

This was following a server reboot.  Stopping dovecot, enabled debug,  
and restarting dovecot restored normal operation.  Rebooting again  
with debug still enabled continued to work normally.