How To remove Postfix banner

[blason]

Hi Folks,

As a security practice I would like to remove the default Postfix banner which I get when I telnet to zimbra on port 25. In a Postfix I know its pretty easy and just matter of changing one line in main.cf. How can that be configured in zimbra? I did check main.cf in /opt/zimbra but some how that setting is not being picked up system and it Postfix consistently appears.

220 zim.int.com ESMTP Postfix

[blason]

OK - i got it should have been added as a separate entry instead of modifying existing entry and restart zmmtactl

[phoenix]

Originally Posted by blason

As a security practice I would like to remove the default Postfix banner which I get when I telnet to zimbra on port 25.

It's required by the standards:

Postfix FAQ
How to change your SMTP banner for fun and profit

[blason]

I completely agree but in a reconnaissance phase the first basic security practice any body recommends is to masquerade the banners because attacker can easily craft the attacks if he gets to know the application running behind.

[FritzBrause]

You need to keep the banner but you're free to remove the "Postfix" part revealing which SMTP Server is actually running. To do this in an update-safe manner use

zmlocalconfig -e postfix_smtpd_banner="\$myhostname ESMTP"
zmmtactl reload

Do not edit main.cf since it will be overwritten.