I’ve previously written a how-to for compiling Postfix from source on a CentOS 5 box. I recently tried following the same steps on a CentOS 6 box, to upgrade from Postfix 2.6.6 which is installed by default.

I’m glad to report that the same instructions will work just fine to upgrade from Postfix 2.6.6 to 2.10. The only difference I found was after the make upgrade command, I saw the following:

Editing /etc/postfix/master.cf, adding missing entry for postscreen TCP service
Editing /etc/postfix/master.cf, adding missing entry for smtpd unix-domain service
Editing /etc/postfix/master.cf, adding missing entry for dnsblog unix-domain service
Editing /etc/postfix/master.cf, adding missing entry for tlsproxy unix-domain service

Which is basically just informing me that the upgrade process tweaked master.cf to support the upgrade.

My CentOS 6 box now reports the following:

# postconf -d | grep mail_version
mail_version = 2.10.0

So feel free to follow these same steps for upgrading a RHEL 6/CentOS 6 box with the default Postfix 2.6.6 to Postfix 2.10 built from source. Good luck!