Qmail (Default Mail Server for Plesk) on Plesk 9.0 sometime start consuming high CPU and overloading server. This sometime happens due to lot of failed message to ‘postmaster’ which overload Qmail. Following is the header of the failed message:

From: MAILER-DAEMON@server.mail.com
To: postmaster@server.mail.com
Subject: failure notice
Date: 10 Apr 2010 02:49:00 +0100
Size: 17540794 bytes
Queue Time: 1270864142 sec
Envelope Recipients (R): webmaster@somedomain.com

In order to fix the problem, please execute following command from the Shell of the Server (root):

[root@support007 ~]# /usr/local/psa/admin/sbin/autoinstaller –select-release-current –install-component base

This will install few micro-updates for Plesk which fix postmaster issues. After that use /usr/local/psa/admin/sbin/mailqueuemng utility to delete messages from qmail queue.

Now the server load will be under control and there will be no failed messages in queue.

[root@vps1846 ~]# /usr/local/psa/admin/sbin/mailqueuemng -s
Messages in local queue: 0
Messages in remote queue: 0
Messages in todo queue: 0
Messages total: 0
Messages found: 0
Timestamp: 1270864534