[c-nsp] Different behaviour for static route on different IOS?

[Gert Doering]

Hi,

On Wed, Feb 16, 2005 at 10:18:33AM +0100, Oliver Boehmer (oboehmer) wrote:
> The behavior reported by Gert in 12.0 with "classful" route looks like a
> corner case (i.e. "ip route 192.168.0.1 255.255.255.0 192.168.20.1" and
> the only route known is 192.168.0.0/16.

Indeed, it's not "classful", but a more generic check "if the route
prefix *and* the gateway IP are part of the *same* supernet route (/16,
default route, ...) --> suppress recursive static route".

The behaviour is not specific to 12.0, but I've also verified this on
12.2/12.2S/12.3.

So the actual surprise might come from the difference between 

  ip route 10.10.10.0/24 255.255.255.0 10.0.0.1 

and

  ip route 11.11.11.0/24 255.255.255.0 10.0.0.1

the first one is ignored if all you have is a route to "10.0.0.0/8"
(because route and gateway IP are both part of 10.0.0.0/8), while the
second one will be installed just fine.

gert
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