The best command to troubleshoot a Plesk Qmail server

[eugenevdm]

Tailing the log file would be the obvious method. But if you have 1000s of mailboxes finding stuff in the mail log is near impossible.

We use:

tail -f /usr/local/psa/var/log/maillog | egrep -i "unable|failed|refused|error|warning|listed"

The only annoying thing is that then the log still produces these stupid warnings:

"server_name spf filter[2873]: Error code: (2) Could not find a valid SPF record"

According to Plesk it's "normal" to have this message:
http://kb.odin.com/6051

The notifications "Error code: (2) Could not find a valid SPF record" and "Failed to query MAIL-FROM: No DNS data for 'domain.tld'" occur in case if sending domain domain.tld does not have valid SPF record in DNS. In this case SPF local rules are not applied.

I disagree, it should be giving you a warning not an error. Anyway, the command is still very good as hopefully you won't have too many SPF events.