Whoops. Broke My Mail Server
I guess more technically I made a DNS change that had unintended consequences.
Recently I've considered changing to Google Apps to host my domains' e-mail. I've been maintaining a mail server continuously since the early 1990s, and frankly I'm getting tired of trying to keep up with those out there that seek to abuse mail servers or that splash the accounts thereon with unwanted junk.
Google Apps offers free domain service for up to 50 accounts, or about ten times as many as I'd really need for the real people. I do have some aliases (like "webmaster" and "postmaster"), but there's only a handful of real accounts. It seemed like it'd be a no-brainer.
I've also got several sub-domains, black-holed so that all of the mail to a domain goes into a single account on the server. These are a little tougher with Google Apps. While Apps supports sub-domains, it doesn't seem to have an easy way to do such "everything goes here" mapping.
All that aside, the DNS change I made allowed me to visit the more convoluted Google URL to get to the mail app into a simple URL that seems to be within my domain. The unintended consequence is that the name I chose to associate is the same that some of the other domains served by the mail server used in their MX records.
I've corrected the error by putting the actual server name in the MX records instead of the alias ('though technically the original DNS entry was an A record, not an alias).
I'd been wondering why I hadn't gotten my morning Dilbert strips. After a little propagation I fully expect to get my full flurry of e-mail again.