Dovecot is not restarted if service dies

[adbenitez]

on VPS with low RAM (ex. mine with 4GB) eventually filtermail and opendkim can use a lot of RAM, I suspect this was the reason Dovecot service got killed/died, in any case, this caused hours of downtime because it coincidentally happened while I was sleeping, if dovecot service would be configured to auto-restart, like filtermail service is, there would have been little downtime, since after filtermail got also killed and restarted the memory usage went down again

TL;DR: please set:

Restart=always
RestartSec=30

for dovecot service same way as it is done for filtermail service so if service dies unexpectedly the server can recover without big downtimes until admin notice or is available

[link2xt]

/usr/lib/systemd/system/dovecot.service says create /etc/systemd/system/dovecot.service.d/service.conf (or rather /etc/systemd/system/dovecot.service.d/10_restart.conf, then put there

[Service]
Restart=always
RestartSec=30

Same should be done for Postfix.

See also https://www.baeldung.com/linux/systemd-modify-config and https://www.freedesktop.org/software/systemd/man/latest/systemd.unit.html