I've so far been unable to make the following work:

I have a small cluster with a master node ( called bayes.bc.edu on the public network, and called master.cl.bc.edu on the internal 10.0.0.0 network). and a number of nodes which are purely on the private network.

I want the master to receive mail and deliver locally (or use .forward and alias rules) to messages sent from the nodes to user@master, and I want it to relay non-local addresses to my campus relay host which is another machine.

The relay part works ok, all mail addressed in a form that my campus relay host recognizes gets delivered. The problem is that mail to

user@master.cl.bc.edu (the internal name) gets relayed to the campus relay which does not know about the host name master.cl.bc.edu because that is defined on a private DNS server for the cluster, and the campus relay rejects the message.

How can I get my cluster master to not relay messages addressed to @master.cl.bc.edu? The queueing/resource manager (torque/pbs) wants to send automatic status messages to user@master.cl.bc.edu and that cannot easily be changed.

Mail MTA is postfix for both master and nodes Some postfix settings on the master.

myhostname = bayes.bc.edu mydomain = bc.edu myorigin = bayes.bc.edu inet_interfaces = master, localhost mynetworks = 10.0.0.0/24, 127.0.0.0/8 relayhost = mail.bc.edu

and some settings on the nodes

mydomain = cl.bc.edu myorigin = bayes.bc.edu inet_interfaces = localhost relayhost = [master.cl.bc.edu]

Thanks for any help, Tony Schreiner