From mboxrd@z Thu Jan  1 00:00:00 1970
From: gtaylor@tnetconsulting.net (Grant Taylor)
Date: Wed, 20 Sep 2017 23:20:21 -0600
Subject: [TUHS] Who is running their own mail server and what do you run?
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Message-ID: <ae53b46a-7b89-922e-98bc-da909f4009d6@tnetconsulting.net>

On 09/20/2017 09:04 PM, Robert Brockway wrote:
> This is a well established technique known as Nolisting.  I believe the 
> safest option is for the port to be unbound and thus for a TCP RST to be 
> sent.
> 
> en.wikipedia.org/wiki/Nolisting

I think I've heard of people doing nolisting before and ran across the 
term within the last week.

I wonder how effective it is.

I recently wrote a gray mail server (in Perl) that ran into the problem 
of the 3rd bullet point in Drawbacks.  -  My workaround has been to 
return ICMP errors, much like nolisting probably does.

I will have to give Nolisting more thought and mess with it.



-- 
Grant. . . .
unix || die