Stop incoming mail if message queue exceeds set value

Gary Pentland gary at
Mon Apr 27 11:46:44 IST 2009


Look here...

Particularly these...

confQUEUE_LA QueueLA [varies] Load average at which queue-only function kicks in. Default values is (8 * numproc) where numproc is the number of processors online (if that can be determined).

confREFUSE_LA RefuseLA [varies] Load average at which incoming SMTP connections are refused. Default values is (12 * numproc) where numproc is the number of processors online (if that can be determined).

confDELAY_LA DelayLA [0] Load average at which sendmail will sleep for one second on most SMTP commands and before accepting connections. 0 means no limit. 

But a few others might be of use.  Be sure you're rejecting invalid recipients during the SMTP dialouge and not at some stage later.  It sounds obvious but can easily be missed and result in 1,000s of messages from a bot being queued and work being done on them, reject these before you queue them!



mailscanner-bounces at wrote:
> I am running a round robin dns mail solution with 4
> mailscanner servers accepting mail.  The problem I am having
> is that on occasion 1 of the servers gets hit with massive
> volumes over a very short time so the queue can grow to 5000+
> in a matter of minutes causing mail delivery delays on that
> specific server.  I would like to be able to set a limit on
> the queue size so that the server stops accepting mail until
> the queue drops below that set value.
> I have tried with sendmail creating 2 cf files but can't get it
> working. Does this have to be managed by mailscanner, r can it be
> done in sendmail? 
> Currently using sendmail-8.14.1 and Mailscanner 4.63.8
> Thanks
> Gordon Colyn
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