[c-nsp] Help settling an argument :-)

[lists at hojmark.org]

> A consistent example of the problem, we have a simple network 
> monitor that pings each interface periodically to see if it 
> is up.  When it pings the DMZ interface, the Novell box 
> answers on the private interface (with a source IP of the DMZ 
> interface).

I pretty sure it will only do that if responding to something,
which is reached via the private interface. Right? (Check the
server's routing table).

> If you're not routing, aren't you always supposed to answer on
> the same interface the traffic came from?

No, not the same *interface*, but the same *address*. (But it's
a very common misunderstanding). Check out RFC1122.

-A