The standard config file for all hosts other than vstout looks like this:
#
# Our domain:
visible domain=vbrew.com
#
# What we name ourselves
visible name=vbrew.com
#
# Smart-host routing: via SMTP to vstout
smart path=vstout
smart transport=smtp
This is very similar to what we used for a UUCP-only site. The main
difference is that the transport used to send mail to the smart host
is, of course, SMTP. The visible_domain attribute makes
smail use the domain name instead of the local hostname on
all outgoing mail.
On the UUCP mail gateway vstout, the config file looks a little different:
# Our hostnames:
hostnames=vbrew.com:vstout.vbrew.com:vstout
#
# What we name ourselves
visible name=vbrew.com
#
# in the uucp world, we're known as vbrew.com
uucp name=vbrew.com
#
# Smart transport: via uucp to moria
smart path=moria
smart transport=uux
#
# we're authoritative for our domain
auth domains=vbrew.com
This config file uses a different scheme to tell smail
what the local host is called. Instead of giving it a list of domains
and letting it find the hostname with a system call, it specifies a list
explicitly. The above list contains both the fully qualified and the
unqualified hostname, and the domain name all by itself. This makes
smail recognize janet@vbrew.com as a local address, and
deliver the message to janet.
The auth_domains variable names the domains for which vstout is considered to be authoritative. That is, if smail receives any mail addressed to host.vbrew.com where host does not name an existing local machine, it rejects the message and returns it to the sender. If this entry isn't present, any such message will be sent to the smart-host, who will return it to vstout, and so on until it is discarded for exceeding the maximum hop count.