I was having problems with keeping the Postfix MTA configured and running with Puppet. Each time Puppet ran it detected that it wasn't running and attempted to start it with no avail.
The error when looking at the service was this:
# service postfix status
master dead but pid file exists
But removing the pid file didn't not help:
# locate postfix|grep pid
/var/spool/postfix/pid
/var/spool/postfix/pid/master.pid
[root@webtest ~]# rm /var/spool/postfix/pid/master.pid
rm: remove regular file `/var/spool/postfix/pid/master.pid'? y
[root@webtest ~]# service postfix status
master dead but subsys locked
So looking at the logs this was seen:
# tail /var/log/maillog
Oct 30 19:44:06 webtest postfix/master[8005]: fatal: bind 127.0.0.1 port 25: Address already in use
Oct 30 20:09:49 webtest postfix/postfix-script[10053]: starting the Postfix mail system
Oct 30 20:09:49 webtest postfix/master[10054]: fatal: bind 127.0.0.1 port 25: Address already in use
Oct 30 20:10:04 webtest postfix/postfix-script[10602]: starting the Postfix mail system
Oct 30 20:10:04 webtest postfix/master[10603]: fatal: bind 127.0.0.1 port 25: Address already in use
Oct 30 20:10:53 webtest postfix/postfix-script[11037]: starting the Postfix mail system
The problem looks like another MTA was running hogging port 25. A quick ps for sendmail revealed nothing, but there's another agent that comes with CentOS 6:
[root@webtest ~]# ps -ef|grep send
root 12448 9780 0 20:16 pts/0 00:00:00 grep send
[root@webtest ~]# ps -ef|grep exim
root 12109 9780 0 20:22 pts/0 00:00:00 grep exim
exim 57456 1 0 Jul07 ? 00:00:00 /usr/sbin/exim -bd -q1h
[root@webtest ~]# service exim stop
Shutting down exim: [ OK ]
[root@webtest ~]# chkconfig exim off
Now a Puppet run should install and run Postfix without a problem:
# puppet agent -t
Notice: Local environment: 'production' doesn't match server specified node environment 'websites', switching agent to 'websites'.
Info: Retrieving pluginfacts
Info: Retrieving plugin
Info: Loading facts
Info: Caching catalog for website.domain.com
Info: Applying configuration version '1477858442'
Notice: /Stage[main]/postfixmta/Service[postfix]/ensure: ensure changed 'stopped' to 'running'
Info: /Stage[main]/postfixmta/Service[postfix]: Unscheduling refresh on Service[postfix]
Notice: Applied catalog in 1.67 seconds
# puppet agent -t
Notice: Local environment: 'production' doesn't match server specified node environment 'websites', switching agent to 'websites'.
Info: Retrieving pluginfacts
Info: Retrieving plugin
Info: Loading facts
Info: Caching catalog for website.domain.com
Info: Applying configuration version '1477858442'
Notice: Applied catalog in 1.46 seconds
