In message <199911051956.OAA06891@melange.gnu.org>, Phillip Rulon writes:
>This might be a little off topic for this list but I am trying this
>hack on a NetBSD box and I suspect that someone here has tried this.

Close enough.  :)

>I have an IP address, say 12.345.67.89 ( not the real one ).  An ISP
>serves this as foo.bar.com, another place serves it as bar.foo.org.
>In principle, an ARP for bar.foo.org should go to foo.org for
>resolution and get handed the IP.  Similarly, a request for
>foo.bar.com should get resolved at bar.com as the same IP.  So both
>domains have an A record for 12.345.67.89.

Okay.

>I thought about CNAMEing
>it but Sendmail wouldn't buy it.

It's not a problem; it's fine for this to be the case.

>I'm a little concerned about what's
>going to happen with rarp or gethostbynumber().  Is this a cool thing
>to do, or am I completely hacking DNS?

It's harmless.  It's just a kind of virtual hosting.

I would put two reverse lookup records, one pointing to each host, although
I'm not sure everyone will like that.  :)

-s