[c-nsp] What is wrong with this config? (nat load sharing)

Randy Bush randy at psg.com
Sun Oct 3 13:00:42 EDT 2004

>> Pointing to interfaces is generally discouraged since it causes the router
>> to want to ARP.  You should point at next hop IP addresses.
> I want to disagree on this one.   
> If the interface is a point-to-point serial link (and dedicated so, unlike 
> a legacy DDR BRI interface), there is no ARP going on, so the config
> above is actually what we strongly recommend to our tech people and to
> our customers.  It's very evident what's going on ("out *that* line"),
> you can run it numbered or unnumbered, without affecting the way static
> routes have to be set up, and in case you need to renumber the interface, 
> you won't need to touch the static routes.

otoh, pointing at next hop lets the remote hands move a
circuit to a new interface, or cut over to a new circuit,
and the noc only has to change the interface part of the
config, not hack through any routing.


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