BuzzSaw Code via Postfix-users:
> We have a mail server running Dovecot (2.3.x) and postfix (3.5.x) on
> RHEL8, using the RPMs from RedHat. Postfix is configured to use the
> Dovecot lmtp for deliveries to the local maildir for each user.
>
> This server uses a virtual user setup, all mail goes under
> /home/vmail/<domain>/<user>/Maildir and the virtual_alias_maps are all
> LDAP based.
>
> We've had a few incidents where we have a large blast of email that
> comes in - usually caused by multiple services and systems all
> reporting a network outage or some other large event.
>
> When that happens, the mail server queue gets backed up, the load on
> the server gets extremely high (30-40),
To avoid high load, reduce the default_process_limit to something
that your VM can handle. I suggest reducing it from the default 100.
postconf default_process_limit = 10
postfix reload
Otherwise you're just running the VM into the ground. Postfix is
an event-driven system, and some VM implementations will lose timer
events and that is what prevents Postfix from working down the queue
without human triggers.
> and these errors pop up in the logs:
>
> postfix/qmgr[ZZZZZZ]: warning: mail for foo.bar.com is using up X of Y
> active queue entries
>
> where X > Y e.g 6040 of 3065 and 'foo.bar.com' is the mail server itself.
The logging may also suggest to change xxx_destination_concurrencly_limit
or to increase the qmgr_message_active_limit. But that does not
help when almost all your mail is going to the same place.
Wietse
_______________________________________________
Postfix-users mailing list -- postfix-users@postfix.org
To unsubscribe send an email to postfix-users-le...@postfix.org
