Even though it is possible to set computer name in Terminal it is not necessary. You can easily do it in System Preferences.
Yesterday I did some more tests. What I wrote about my nephew's Mac (High Sierra) is also valid for Sierra. So nothing has changed between 10.12 and 10.13.
And I'm gonna tell you why.
Naming convention for NetBIOS name is that the name can be at most 16 alphanumeric characters long. User can assign 15 characters. The 16th is reserved.
Read here for reference.
In macOS the computer name can be longer. What you choose there, is also assigned to NetBIOS name. You can assign a different name if you want, from within WINS, but you must follow NetBIOS naming convention. If computer name is less then 15 characters, NetBIOS name will be the same as computer name. Otherwise it'll take a "pseudo" random name. I quoted pseudo because it is not random at all. In my testing, for a very long computer name, the NetBIOS name was set to MACBOOAIR-1B52. The first ten characters are obvious, the 11th character is always a dash and the remaining 4 are the last 2 hexadecimal figures of the network adapter MAC address.
Now you have some oddities. That's why I told you a few messages earlier that Vodafone station is playing dirty.
Now to confirm that my theory about VF station is true, please turn it off until your computer name settings are in place.
Assign to computer name a 15 chars or less, name. I wouldn't use spaces. I'll stick to letters and numbers only. But it's up to you.
Check if NetBIOS name has changed accordingly. If not, choose another name of your choice but lesser than 15 chars. Press enter to confirm.
Click OK then Applica, then close System Preferences.
Open System Prefereces and check again that NetBIOS name hasn't changed.
If all is fine. Turn back on Vodafone station.
Let me know
