DNS for Mail
 

Hi all,
I was wondering if anyone could point me to some good how-to articles that deal specifically with DNS configuration as it relates to mail routing. I know there is a DNS-howto, but I was looking for something a little more specific.

Thanks!
-Pair

O'reilly's DNS and Bind.

BAAMMM!

DNS & BIND is excellent.

For "mail routing" (at least, from the Internet) all you need is at least one MX record.

yourdomain.tld. IN MX 20 yourmailserver.yourdomain.tld.

The "20" is the preference. The higher the preference number, the less preferred it is. The lower the number, the more preferred. Other mail servers will start at the lowest number and try each listed MX in ascending order until they find one that will take the mail (roughly speaking, it's actually more complicated than that, but you can assume that it works the way I said and you'll be OK).

That was kinda what I was thinking, but don't you need PTR records for servers that do reverse DNS? What about an A record?

Pair

Well how are they going to resolve the IP of "yourmailserver.yourdomain.tld" without an A record??? Of course you need an A record! As for PTR records, they're not strictly required, but they certainly are polite. Every IP should have a PTR record.