smart_host on sendmail min config

[Mark Tinguely]

It has been a long time since I tested rule sets, but try this:

(system prompt)$ sendmail -bt
ADDRESS TEST MODE (ruleset 3 NOT automatically invoked)
Enter <ruleset> <address>
> 3,0 user at gmail.com

Sendmail will print the rules it uses to parse the address. It should end
with something like:

 parse            returns: $# relay $@ YOUR . SMARTMAILER . DOMAIN $: user < @ gmail . com . >

Where YOUR.SMARTMAILER.DOMAIN is defined in your /etc/mail/sendmail.cf
as your relay mailer.

It should return your smart mailer even if the mail address does not resolve,
the smart mailer.

--Mark Tinguely.