I’ve experienced a loss of service about the same time (11am ish) for two days running.
The status page shows:
Dovecot LMTP LDA is not running (port 10026).
IMAPS (dovecot) is not running (port 993).
Mail Filters (Sieve/dovecot) is not running (port 4190).
A restart on both occasions resolved (yesterday I ran an upgrade/update before restart and today I noted the box was indicating it needed a Reboot from the status page so actioned that). No further changes have been made.
Reviewing mail.log isn’t throwing up anything obvious. mail.err is showing the following but unsure if this timing co-incides:
Aug 20 11:45:18 box postfix/submission/smtpd[151387]: fatal: no SASL authentication mechanisms
Aug 20 11:46:56 box spampd[149402]: WARNING!! Error in process_request eval block: /usr/sbin/spampd: socket connect failure: Connection refused
Just wondering if others have experienced similar.
If anyone can help guide on investigative routes I would appreciate it. If not I’ll continue to monitor over the next fews days.