> On 01/06/2021 10:59 Volker Stolz <[email protected]> wrote: > > > I just dealt with an interesting Dovecot issue on our small server, and > thought I might share it. I also feel that although in the end it was a > configuration error, Dovecot should somehow avoid leaving this processes > around and hence filling up the process limit quickly. > > - set up Dovecot IMAP on Debian buster (either with the older 2.3.x Debian > package, or 2.3.14 from the dovecot-repo) > - config: > ... > namespace inbox { > inbox = yes > location = > ... default settings ... > ... > passdb { > args = scheme=HMAC-MD5 username_format=%u /etc/dovecot/users > driver = passwd-file > } > protocols = " imap" > ... > userdb { > args = blocking=no > driver = passwd > } > ... > - secret sauce: have a user in the passdb that doesn't have a physical > account on the system yet (we were migrating to a new machine). > > The log-file shows successful authentication for that user (after we flipped > DNS to point to this new machine), but over time (2-3 times/day) we were left > with an increasing number of `imap-login` processes in state `pre-login`, > eventually requiring a dovecot restart. Dialling up process_limits didn't > seem to help, we'd just get more of these stale processes. > > After creating the user on the system, the behaviour reverted to normal, no > more stale processes. I do not know what error message that user received on > their end, but since we announced we were migrating, they probably just > ignored it and thought it as part of the transition. > > Best, > Volker (a happy & long Dovecot user)
Hi Volker, can you please post full `doveconf -n` output, please? Aki
