Hi,
Web search turned no results to this problem:
We have a small site running private e-mail for maybe 12 people, dovecot is used by Postfix-SASL and IMAP clients.
PROBLEM: When starting dovecot, after a few hours, IMAP clients are no longer able to connect. Thunderbird indicates that connection is refused.
On the server, we see 100 dovecot/imap-login processes. This is the process limit. If we increase the process limit to 200, same thing, we survive a few hours longer but eventually we're seeing 200 imap-login processes and rejected connections.
When listing TCP connections via lsof, there are only around 30 connections open to IMAP and we have exactly the same amount of dovecot/imap processes. These connections are held by 30 dovecot/imap-login processes.
The other 70 dovecot/imap-login processes seem to do nothing. They're all sitting in "epoll_wait(14," according to strace but don't have TCP connections open.
The only way out of this that we have found is re-starting dovecot every few hours.
BTW, service_count = 1 for improved security. Dovecot Version: 2.3.4.1 (f79e8e7e4)
Interestingly we were using nearly the same config on our old server with 2.2.13 and did not see this issue.
Any ideas how to solve that properly?
Thank you, Wolfgang