Static Routing 172.16.0.0/32
swmike at swm.pp.se
Sun Dec 10 19:16:21 CST 2017
On Fri, 8 Dec 2017, Ryan Hamel wrote:
> 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).
> I would to hear everyone's thoughts on this, as this the first IP
> address in an RFC1918 range.
Last time I tried using the first address of a classful address block
(which 172.16.0.0/32 would be) in Cisco IOS (classic), that didn't work
properly. This was in IOS 12.0.x. You can't set up BGP peers to something
in the network address in classful network space, for instance. So
172.16.0.0/32 or 172.16.255.255/32 wouldn't work (because it's first and
last address of class B space), but 172.16.1.0 worked just fine (because
in class B space, 172.16.1.0 isn't special).
So while this has been allowed per standardssince mid 90:ties, it's not
obvious that it'll work in all operating systems that might still be in
Mikael Abrahamsson email: swmike at swm.pp.se
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