Wednesday, April 18, 2012

/etc/sysconfig/sendmail

SkyHi @ Wednesday, April 18, 2012
Next up is /etc/sysconfig/sendmail. This file is used to assign some simple variables for the sendmail initialization script. By default it contains the following information:
DAEMON=yes
    QUEUE=1h
    
Quite simply this information is passed to the sendmail initscripts telling sendmail to run as a daemon and that it should process its queue once an hour. Depending on your environment you may need to change these values. If you're running a 24x7 net host, you should know that the SMTP RFCs specify a minimum queue time of 5 minutes so a queue run frequency of one minute would violate the RFC specifications.

Change the Queue Runner Interval in Sendmail
The default in CentOS 5.x is 1 hour:
# pgrep -lf "Queue runner"
12443 sendmail: Queue runner@01:00:00 for /var/spool/clientmqueue
You can change it editing /etc/sysconfig/sendmail (ie. set 30 minutes):
DAEMON=yes
QUEUE=30m
It’s easy, isn’t it? Useful for mail backup MXs that may need shorter queue run times.


REFERENCES
http://www.redhat.com/support/resources/howto/RH-sendmail-HOWTO/x95.html
http://www.redhat.com/support/resources/faqs/RH-sendmail-FAQ/x190.html
http://www.cyberciti.biz/tips/force-sendmail-to-deliver-a-message-in-sendmails-mail-queue.html