I've run into a problem I've never had before and could use some help.
I recently moved several sites from one dedicated server to another using CPanel's site move feature.
I didn't have any problems. I thought.
All my sites work fine but when I went to go to the control panel to a few of the bigger sites the site control panels don't exist. The simply aren't there. With that said some of the other sites from the move do have control panels.
Has anyone seen this before? Is there a way to rebuild the control panel without affecting the site?
If I've understood your problem, this usually happens when /tmp in the source server has not enough room for temporary files. If your site is bigger than /tmp, the account in the destination server will be empty.
Hmm, if the port doesn't work either, then it can't be an alias problem which I thought it was...
Go directly to your IP address, and add on the port for CPanel, e.g.: http://255.255.255.255:2082 (If that doesn't show, then you're screwed).
Then try logging in with the username and password of an account who's control panel doesn't work.
If all this works, it really sounds like a DNS issue (or incorrectly configured firewall perhaps?). If you are running a firewall, i'd check over it. Apart from that, I don't see how this problem can occur (you may wish to give all your users access to the CP by emailing them with the IP and port as shown above, if that works...).