Static Routing 172.16.0.0/32

Fri Dec 8 21:55:34 UTC 2017

> At some point, some chucklehead  is going to look at that .0.0 and mentally think /16, and things will go pear-shaped pretty quickly....

Same for a /12, which is RFC1918.

-------- Original message --------
From: valdis.kletnieks at vt.edu
Date: 12/8/17 1:46 PM (GMT-08:00)
To: Ryan Hamel <Ryan.Hamel at quadranet.com>
Cc: nanog at nanog.org
Subject: Re: Static Routing 172.16.0.0/32

On Fri, 08 Dec 2017 03:13:57 +0000, Ryan Hamel said:
> Greetings,

> A colleague of mine has static routed 172.16.0.0/32 to a usable IP address,
> to have a single known IP address be static routed to a regions closest server.
> While I understand the IP address does work (pings and what not), I don't feel
> this should be the proper IP address used, but something more feasible like a
> usable IP in a dedicated range (172.31.0.0/24 for example).

Probably depends on what your colleague is trying to do.  Nothing in the
rules says the .0 address on a subnet is reserved (though you're in for a
surprise if there's any gear still on the net with a 4.2BSD stack).

> I would to hear everyone's thoughts on this, as this the first IP address in
> an RFC1918 range.

> At some point, some chucklehead  is going to look at that .0.0 and mentally think /16, and things will go pear-shaped pretty quickly....