[afnog] Failing to receive inbound emails

[Stephane Bortzmeyer]

OK, let me restate what I understand of your setup. You have only one
public IPv4 address (a good reason to move to IPv6, by the way) for
the entire university. You use a PIX box to redirect traffic to
internal servers. Therefore, traffic to port 25 can only go to one
email server and, for reasons I do not know, you want to have two
email servers, each serving a different set of domains. Correct?

A possible solution is to have the "public" email server relay to the
second server. In Postfix parlance (untested):

relay_domains = /etc/postfix/relay
transport_maps = hash:/etc/postfix/transport

In relay:

yyyyy.ac.zw

In transport:

yyyyy.ac.zw smtp:[192.168.1.10]

And don't forget postmap, reload, etc.