dovecot - Dec 2009 - dovecot: pipe() failed: Too many open files

In the past few months we've been having increasing problems with dovecot 
timing out pop3 logins.

As best I can tell it gets to the point where it won't accept any new pop3 
logins.

The error in the mail log is:

dovecot: pipe() failed: Too many open files

I've researched this problem a number of times, usually I see suggestions to
increase ulimit.

I've done this a number of times, all the way up to:

ulimit -n 8192

I've put that in the init script right above the daemon start line.

So far it hasn't helped.

In addition, when looking at lsof, it doesn't seem like we're anywhere
near
the actual limit. for example, last time dovecot only had 1032 files open.

Does anyone have any idea what could be causing the error? Or what else I can 
try to figure this out?

Thank you,

	JW

-- 

----------------------
System Administrator - Cedar Creek Software
http://www.cedarcreeksoftware.com

On Dec 18, 2009, at 4:47 PM, JW wrote:
> I've researched this problem a number of times, usually I see
suggestions to
> increase ulimit.
> 
> I've done this a number of times, all the way up to:
> 
> ulimit -n 8192
> 
> I've put that in the init script right above the daemon start line.
What exactly is the "daemon start line"? Many Linux distros override
ulimit in their internal scripts. If you're using Linux, you could check if
dovecot process really has 8192 limit:

cat /proc/`pidof dovecot`/limits | grep 'Max open'