Are your subdomains in order?

I was recently trying to recall a subdomain (for example: I had set up for a client, and tried guessing at what I thought it was. While I guessed wrong, it highlighted an important issue to address.

Wildcard DNS

The subdomain I tried was not an actual site for the client, but a wildcard DNS entry was sending it to the IP of the server anyways. If you have a wildcard entry set up for your domain(s) you should take care to see what your web server is serving up for subdomains you aren’t actually using. In most cases, it will serve up the default site for that IP address, but under whatever URL you used. (more…)