Delivery Temporarily Suspended Unknown Mail Transport Error Postfix Upd [top] <RECENT>

If you use MySQL, PostgreSQL, or LDAP for virtual domains, a slow query or a temporary database connection drop will trigger this error. Postfix can’t determine the final delivery method, so it throws its hands up.

Are you using a (like Amavis or Rspamd)? Is this happening for all domains or just one? What Linux distribution are you running? Share public link If you use MySQL, PostgreSQL, or LDAP for

To apply changes, always restart the service using systemctl restart postfix or postfix reload . If you use MySQL