Check manual page of postfix_mailq
Length of the postfix mailqueues
This check monitors the number of deferred mails in the outgoing mail
queue, as sent by the linux agent of Check_MK. Depending on the version
of the Check_MK agent the number of mails in the active queue is monitored
This check creates one service per host which represents the state
of the mailqueues.
The check will result in WARNING/CRITICAL states when the number of items
in the queues have reached the defined thresholds.
On each system which provides the postconf command one service is created.