[OpenAFS] HOWTO: multiple cells on a single machine

Marcus Watts mdw@umich.edu
Tue, 23 May 2006 15:03:11 -0400

Ken Hornstein <kenh@cmf.nrl.navy.mil> wonders:
> >So,, etc could be used?
> I've never seen a machine with a interface.  Loopback is generally
> sort of magical; I don't think you can have more than one (certainly not in
> a portable way).  In theory, you could pick different port numbers ...
> but how you configure that is an open question.

ntp seems to like using "ip addresses" like that for local time sources.
I don't think they correspond to anything the kernel knows about though.

Above Derrick proposed using an authenticated RPC; that seems
best.  volserver didn't use it historically because it relied
on the fact this was (a) fast to (b) cheat on locking issues (by blocking
on the socket until the response came back).  Assumption (a) hasn't
been true ever since nat.  With pthreads (b) becomes a moot point so using
an RPC should be trivial.  Using the unix domain socket is possible as
well and even argueably a bit more secure, but not quite as elegant.
Presumably 'chroot' could be used for multiple local fileserver
instances in that case.