> From:David F. Skoll > Sent: Monday, January 16, 2006 8:58 AM > > > Kris Deugau wrote: > > > define(`confQUEUE_LA', `2')dnl > > define(`confREFUSE_LA', `7')dnl > > Bad settings. > > Having REFUSE_LA higher than QUEUE_LA is a surefire way to kill > your server.
Some handy tuning/debugging tips: http://www.brandonhutchinson.com/Miscellaneous_Sendmail_notes.html Quoting: "rejecting connections on daemon MTA" By default, Sendmail will reject MTA/MSA connections when the system load is 12 * number of processors, and operate in queue-only mode when system load is 8 * number of processors. egrep "QueueLA|RefuseLA" /etc/mail/sendmail.cf #O QueueLA=8 #O RefuseLA=12 >From cf/README: 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). For dedicated mail servers, the value of RefuseLA should be greater than the value of QueueLA. Mail should not be accepted faster than it can be processed, as mentioned in sendmail/TUNING: It is important not to accept mail faster than it can be delivered otherwise the system will be overwhelmed. Hence RefuseLA should be lower than QueueLA, the number of daemon children should probably be lower than the number of queue runnners (MaxChildren vs. MaxQueueChildren). Also, read this comp.mail.sendmail post http://groups.google.com/group/comp.mail.sendmail/msg/41d65caec2a4edb3?hl=en &lr=&ie=UTF-8 On a dedicated mail server, you want to set QueueLA *higher* than RefuseLA - the other way around will cause your queue to explode when the load is high (assuming you reach QueueLA of course), you accept lots of new messages but can't get rid of them as the load average hovers around RefuseLA - the many messages in the queue drive up disk I/O and thereby the load average. The default of QueueLA lower than RefuseLA only makes sense for a server that does other things besides mail, where you want to reduce the impact of the mail load on the other functions by queuing instead of delivering when the load is high. _______________________________________________ NOTE: If there is a disclaimer or other legal boilerplate in the above message, it is NULL AND VOID. You may ignore it. Visit http://www.mimedefang.org and http://www.roaringpenguin.com MIMEDefang mailing list [email protected] http://lists.roaringpenguin.com/mailman/listinfo/mimedefang
