Stop incoming mail if message queue exceeds set value

[Gary Pentland]

Well, there are many options... confMAX_DAEMON_CHILDREN, and confCONNECTION_RATE_THROTTLE will control how many open connections / concurrently accepted connections there are...  Setting these low(ish)will help.

http://www.milter.info/sendmail/milter-limit/  is another option.

Depending on what you want to achieve, and how big your budget is, some proper network load balancing may be another answer.

Gary

mailscanner-bounces at lists.mailscanner.info wrote:
> Thanks, have implemented these already.  The issue is not on
> the load, the load stays pretty under control.  I just want
> to stop accepting mail on the
> 1 server so the mails are forced to go to the other servers,
> i.e. 1000 messages handled by 4 servers will be quicker than 1000
> mails handled by 1... 
> 
> 
> 
> -----Original Message-----
> From: mailscanner-bounces at lists.mailscanner.info
> [mailto:mailscanner-bounces at lists.mailscanner.info] On Behalf
> Of Gary Pentland
> Sent: 27 April 2009 12:47 PM
> To: 'MailScanner discussion'
> Subject: RE: Stop incoming mail if message queue exceeds set value
> 
> Hi,
> 
> Look here...
> 
> http://www.sendmail.org/m4/tweaking_config.html
> 
> 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!
> 
> Regards,
> 
> Gary
> 
> 
> mailscanner-bounces at lists.mailscanner.info 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
>> Office : 086 123 ITNT (4868)
>> Cell : 083 296 7534
>> Fax : 086 520 0885
>> InTheNet Technologies
>> www.itnt.co.za
>> MSN:gordoncolyn at hotmail.com
>> SKYPE:gordoncolyn <skype:gordoncolyn?call>
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