Change OSX Hostname - For Real!

This was enough of a headache today that I wanted to keep a record.

If the hostname of your MacBook doesn't match across various places (Terminal, System Preferences, iCloud) - you can fix it with the steps in this Ask Different question.

I've also included the answer here, for my own sanity.

Setting the Mac hostname or computer name from the terminal

1. Open a terminal.
2. Type the following command to change the primary hostname of your Mac:
   This is your fully qualified hostname, for example myMac.domain.com

   sudo scutil --set HostName <new host name>
   

3. Type the following command to change the Bonjour hostname of your Mac:
   This is the name usable on the local network, for example myMac.local.

   sudo scutil --set LocalHostName <new host name>
   

4. If you also want to change the computer name, type the following command:
   This is the user-friendly computer name you see in Finder, for example myMac.

   sudo scutil --set ComputerName <new name>
   

5. Flush the DNS cache by typing:

   dscacheutil -flushcache
   

6. Restart your Mac.