So you’ve renamed your SQL Server, but something isn’t right.
Returns the old name.
The fix is simple.
You just need to restart the SQL instance and @@servername will return the correct name.
More info on the Microsoft Docs.
On a similar note, Octopus Deploy has similar annoyance, the server name doesn’t update for the server node. Again simple fix for this simple annoyance:
The other thing that can get missed is the SQL Jobs.