[Dovecot] avoid log message when using nagios check

[Daniel Parthey]

Timo Sirainen <tss at iki.fi> schrieb:
>On 10.7.2013, at 21.48, Kelsey Cummings <kgc at corp.sonic.net> wrote:
>
>>> This is fine for the nagios checks, but we are facing similar
>>> problems with our loadbalancer, which is just doing TCP Healthchecks
>>> on the IMAP/POP3/SIEVE ports, so being able to disable the warning
>>> for trusted networks would be really helpful.
>> 
>> Same here.  We use LVS with surealived and LUA scripting to do a
>complete login/logout cycle as part of the health check.  Even the
>ancient Alteon's had similar functionality (and supported common
>protocols like pop and imap out of the box.)
>
>So it would have to disable logging also for the logout message after
>login.. Can those load balancers be configured to send these kind of
>extra XCLIENT/ID commands? Is it really worth the effort that it really
>works in enough systems?

No. It does simple TCP connects, doesn't know about IMAP at all and won't send any string, it just checks if the TCP port is available. Would it be a problem to remove the log message altogether, at least for trusted IPs or make it a warning, not an error. What is so bad with TCP connects/disconnects without any IMAP traffic, especially when they originate from trusted IPs?