Yes, this has been on here before, but I have never seen a consise answer to the question. Many ISPs block port 25 for our users from home and they use Thunderbird, etc. We are about to migrate over to Zimbra for all 1600 users and I am doing testing before we go to our ownership.
On our existing postfix setup, we have an entry in master.cf:
8025 inet n - n - - smtpd
To allow users to send via port 8025. Since we already have this setup on our existing, and wont have to have users change setup on their machines, does anyone see any problems to this?
To add an additional listener port of 2525, insert the the following line in /opt/zimbra/postfix/conf/master.cf
2525 inet n - n - - smtpd
Then, restart the MTA:
# su - zimbra
# zmmtactl stop
# zmmtactl start
* Do not attempt to bind to ports in use by other applications. This will cause the MTA or other application to fail.
* Backup /opt/zimbra/postfix/master.cf before an upgrade. Changes made to master.cf should only be applied to the current distribution after upgrading.
There's a concise answer in the wiki and it's in the forums, IIRC.
Originally Posted by vaitguy