How to install a more recent postfix on centos 6

It is quite simple to install a more recent postfix version on centos 6.

Just do:

vi /etc/yum.repos.d/epel-postfix.repo

[epel-postfix]
name=Latest upstream Postfix 2.9.x and 2.10.x release for RHEL6
baseurl=http://repos.fedorapeople.org/repos/mstevens/postfix/epel-$releasever/$basearch/
enabled=1
skip_if_unavailable=1
gpgcheck=0

[epel-postfix-source]
name=Latest upstream Postfix 2.9.x and 2.10.x release for RHEL6 - Source
baseurl=http://repos.fedorapeople.org/repos/mstevens/postfix/epel-$releasever/SRPMS
enabled=0
skip_if_unavailable=1
gpgcheck=0

Then do a regular yum update.