From: Pandu Poluan <pandu@poluan.info>
To: Gentoo-user@lists.gentoo.org
Subject: [gentoo-user] Portknock before Postfix delivery?
Date: Mon, 4 Jul 2011 08:31:10 +0700 [thread overview]
Message-ID: <CAA2qdGXHV9_zu0YNsX5c5rFVE2yu-E1t5TA+6T2P=DEiwaGApA@mail.gmail.com> (raw)
I'm just wondering...
I'm implementing an email gateway using postfix. The gateway lives as
a VM in my ISP, and it will deliver 'accepted' emails to the company's
email server which lives in the DMZ. The email server's port is
shifted to a non-25 external port number.
So far so good. However, a portscanner might still be able to detect
which port is open and attempt deliveries there.
So, the question: Is it possible to configure the system in some way
so that Postfix will first perform a portknocking before attempting
delivery to the internal mail server?
If that is not possible, what solution would you recommend to 'harden'
the non-25 mail port?
Rgds,
--
--
Pandu E Poluan - IT Optimizer
My website: http://pandu.poluan.info/
next reply other threads:[~2011-07-04 1:32 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-07-04 1:31 Pandu Poluan [this message]
2011-07-04 2:55 ` [gentoo-user] Portknock before Postfix delivery? Walter Dnes
2011-07-04 10:14 ` Pandu Poluan
2011-07-04 7:22 ` Neil Bothwick
2011-07-04 10:15 ` Pandu Poluan
2011-07-04 12:49 ` Neil Bothwick
2011-07-04 13:46 ` Michael Orlitzky
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