Subject: Re: routing
To: None <current-users@NetBSD.ORG>
From: der Mouse <mouse@Rodents.Montreal.QC.CA>
List: current-users
Date: 09/10/1997 07:24:34
>>> The route command accepts a flag "-interface", where instead of
>>> specifying a remote gateway to the destination, you specify the
>>> local address of an interface which will be used to transmit to the
>>> directly reachable destination.

>>> Does that already do what you want, or am I missing something?

Well, first, it works only for directly reachable destinations; it is
no help at all when the target is behind a gateway and you want to
specify the interface to be used to reach the gateway.  (For the
much-cited case of PPP, though, the difference may not matter.  For a
broadcast medium with something akin to ARP on it, though, it does.)

>> Not if you have several interfaces with the same IP address, [...]

> I'm confused.  Why would this change just because you have more than
> one interface with the same IP address?  If you tell it to go out a
> particular interface, which the -interface flag is documented to do,
> then who cares what the address of that function is, as long as the
> packet goes out it?

The problem is that -interface doesn't take an interface name; it takes
an interface local address.  Therefore, when you have multiple
interfaces with the same local address, there is nothing you can pass
to -interface that names one of them as distinct from the others.

					der Mouse

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