Configure Webmin to send an e-mail notification if Postfix mail queue reaches certain threshold

We receive lots of automatic notifications from Webmin on various aspects of services running on our servers. Would be very nice if Webmin could also notify when Postfix mail queue gets too big - good sign of some malicious script sending massive e-mail messages - so that admin could take measures.

Thanks for consideration!



Howdy -- that feature is supported today, actually.

To configure that, you can go into Webmin -> Others -> System and Server Status, and there, setup a new monitor of type "Mail Queue Size".

Then, you can choose how large it needs to be before you are notified of the issue.

Eric, thanks for the input. I knew about that setting, but the problem with that option is that e-mail messages can have different sizes and the idea was to rely on number of messages in the queue that Virtlamin seems to be already able to calculate. Would be nice to se threshold to let's say 500 messages regardless of what sizes of each of them has.

The "Mail Queue Size" monitor should actually be based on number of messages in the queue, rather than file size.

That is, if you set "Maximum mail queue size" to "500", it should notify you if the queue reaches 500 email messages.

Were you seeing something different in your testing though?

Excellent. I was mistaken by wording of the setting "Mail Queue Size", but never tested this. Maybe you can change this to "Mail Queue Quantity" to make it more clear?