Steve Jones fixes a naming issue on his SQL on Linux installation:
I setup a new instance of SQL Server on Linux some time ago. At the time, the Linux machine didn’t have any Samba running, and no real “name” on the network. As a result, after installing SQL Server I got a NULL when running SELECT @@SERVERNAME.
The fix is easy. It’s what you’d do if you had the wrong name.
Read on for the command, and don’t forget to restart the database engine afterward.