I’ve just bumped into this little chestnut again, and thought it would be worth documenting quickly, once and for all.
If you run Mac OS X Server, the one thing that is more important than anything else is to make sure the DNS hostname is set correctly. It’s fundamental – everything breaks if it’s not working. Out of the box, Server even configures its own DNS server to make sure the details are correct.
Now, I run my own internal DNS using Mac OS X Server, just so I don’t need to remember IP addresses. However, after adding an address to the DNS yesterday, the hostname of the server magically changed. I didn’t ask it to, it just happened. It was time to break out the repair tools.
Three Commands Will Save You
dscacheutil. Remember them, because they are your only friends. If the DNS is iffy, Server Admin runs away and needs some coaxing to play again (which, of course, is really helpful).
First, make sure that your IP address is correct. Please tell me you’re using a static IP? Yes? Good. If that’s not the issue, fire up Terminal.app and find out what’s going on. My first hint was that the hostname next to my command prompt had changed, which is a pretty big clue. Run: