[dns-operations] An interesting over-optimization for "postmaster"

[Paul Hoffman]

Greetings again. Just a heads-up about some scripts running on some ISP's DNS-serving boxes. A friend of mine has a domain, call it somedomain.com, with a few boxes on it. He named his SMTP server "postmaster.somedomain.com" because that is what was recommended in something he read as he was setting up the box. He had no problems with this setup for many years until he moved his service to a new ISP.

That ISP gets points for allowing its customers to set their own reverse-lookup address names. They lose points for having a script (that seems to run weekly) that looks for "postmaster.somedomain.com" in the database and turn that into "postmaster at somedomain.com", thereby screwing the PTR record completely and causing overly-picky SMTP receivers to say that the SMTP server has no valid reverse address.

Changing the host name to "mail.somedomain.com" and using that in the ISP's interface for reverse-lookup addresses has worked for more than the normal breakage cycle.

Takeaway: "postmaster" is not special. (The same is probably true for "abuse" and "root" and even "whois".)

--Paul Hoffman