Timeout problems

[r.felber at ek-muc.de]

On Wed, Oct 20, 2010 at 01:45:15PM -0700, Eric Deis wrote:
> There is nothing relevant in /var/log/messages, definitely no errors. 
> Don't have the other logs mentioned.
> 
> I included an excerpt previously of what was happening in maillog:
> Oct 19 21:14:37 MYSERVER postfix/smtpd[5696]: connect from
> smtp14.icpbounce.com[216.27.93.112]
> Oct 19 21:16:23 MYSERVER postfix/smtpd[5696]: warning: timeout on
> 127.0.0.1:12525 while reading input attribute name
> Oct 19 21:16:23 MYSERVER postfix/smtpd[5696]: warning: problem talking to
> server 127.0.0.1:12525: Connection timed out
> Oct 19 21:18:04 MYSERVER postfix/smtpd[5696]: warning: timeout on
> 127.0.0.1:12525 while reading input attribute name
> Oct 19 21:18:04 MYSERVER postfix/smtpd[5696]: warning: problem talking to
> server 127.0.0.1:12525: Connection timed out
> Oct 19 21:18:04 MYSERVER postfix/smtpd[5696]: NOQUEUE: reject: RCPT from
> smtp14.icpbounce.com[216.27.93.112]: 451 4.3.5 Server configuration
> problem; from=<bounces+454705.29871415.356246 at icpbounce.com>
> to=<gabriela at MYCLIENTDOMAIN.COM> proto=ESMTP helo=<smtp14.icpbounce.com>
> Oct 19 21:18:04 MYSERVER postfix/smtpd[5696]: disconnect from
> smtp14.icpbounce.com[216.27.93.112]
> 
> 
> Doing some more research, perhaps my local DNS cache was not setup properly.

I don't think that was the issue.

> /etc/resolve.conf was missing the following line:
> nameserver 127.0.0.1
> 
> Only had references to my actual name servers. BIND is running. Did some 
> dig queries, and looks like the cache is working. First query will take 
> 100-200ms or less. Second query 1ms or 2ms, indicating cache.


> I will just wait and see if the errors show up again. Quite random. Once 
> in three months, then once per week, and then daily. Is there anyway to 
> test and force the error?

Once that error occurs frequently one could setup a strace which follows
forks on the master and its children.

I see that not as a realistic option.

I will insert some debug symbols for the listen-stuff in the next
days. 


-- 
	Robert Felber, PGP: D1B2F2E5