Thank you very much for your help, I cross mi fingers but it seems that this was the problem.
Fabio Ferrari
On 26.10.2012, at 13.24, FABIO FERRARI wrote:
Hi all,
we have a problem about anvil, it seems that when we have a high load the dovecot stops to work. Sometimes it is sufficient to make a dovecot reload, but sometimes we have to restart it.
Oct 26 11:13:55 anvil: Error: net_accept() failed: Too many open files
This is the problem.
And these are the limit settings in the OS:
soft nofile 131072
hard nofile 131072
Have someone had the same problem?
The OS limits are ok. But you need to make sure that the dovecot processes have enough fds in ulimit. You can check the limits with:
cat /proc/<pid of anvil process>/limits
The "Max open files" soft limit is what you're most likely hitting. Use "ulimit -n 10000" or something before running dovecot binary. And make sure that it changes the limit in the proc. Many init scripts change the ulimit internally.