D. J. Bernstein
Internet mail
qmail
Frequently asked questions

Routing outgoing messages

How do I set up a separate queue for a SLIP/PPP link?

Answer: Use serialmail.

How do I send local messages to another host? All the mail for af.mil should be delivered to our disk server, pokey.af.mil. I've set up an MX record for af.mil in DNS. The problem is that we also have a machine named af.mil; when a user on that host sends a message to af.mil, af.mil tries to deliver it locally. How do I stop that?

Answer: Remove af.mil from /var/qmail/control/locals, and tell qmail to read locals. Make sure the MX is set up properly before you do this. Also make sure that pokey can receive mail for af.mil.

How do I set up a null client? I'd like zippy.af.mil to send all mail to bigbang.af.mil.

Answer:

     echo :bigbang.af.mil > /var/qmail/control/smtproutes
     chmod 644 /var/qmail/control/smtproutes

Make sure to disable local delivery. Also turn off qmail-smtpd in /etc/inetd.conf, and give inetd a HUP.

How do I send outgoing mail through UUCP? I need qmail to send all outgoing mail via UUCP to my upstream UUCP site, gonzo.

Answer: Put

     :alias-uucp

into /var/qmail/control/virtualdomains, and tell qmail to read virtualdomains. Put

     |preline -df /usr/bin/uux - -r -gC -a"${SENDER:-MAILER-DAEMON}" gonzo!rmail "($DEFAULT@$HOST)"

(all on one line) into ~alias/.qmail-uucp-default. (For some UUCP software you will need to use -d instead of -df.)

How do I deal with ``CNAME lookup failed temporarily''? The log showed that a message was deferred for this reason. Why is qmail doing CNAME lookups, anyway?

Answer: The SMTP standard does not permit aliased hostnames, so qmail has to do a CNAME lookup in DNS for every recipient host. ``CNAME lookup failed temporarily'' means that the relevant DNS server is down. qmail will try again soon.