If you are trying to setup Database Mirroring, it prefers to see a FQDN for the servers when entering partner information. If you don’t you’ll get following error message:
This message will not go away if you are setting up mirroring on Standalone or Workgroup computer because you cannot qualify your computer name. When setting up mirroring using the GUI interface and when you reach the following dialogbox:
In this dialog box click ‘DO NOT START MIRRORING’. Once you do that you will return to the Database Mirroring options dialog in which following three fields need to be edited:
The three boxes in the red will have the TCP://ComputerName:Port there; replace those with the IP address instead. So if everything is running on one computer, change principal address to TCP://127.0.0.1:5200, mirror address to TCP://127.0.0.1:5201, and witness address to TCP://127.0.0.1:5202 and then click ‘Start Mirroring’.