We are running a SAMBA "Domain" - is it possible on a Windows server to run WSUS without a "proper" Windows domain and would our SAMBA controlled clients use this server?
We are not so much worried about managing the clients, more caching the updates themselves (approval of the updates would be good too).
And the answer is yes...
http://technet.microsoft.com/en-us/library/cc720532%28WS.10%29.aspx
More searching before asking next time!
You can do as Jon suggests through the GUI if you have one or too machines. You can manipulate the setting in the registry. With SAMBA you should be able to set a login script, so export the keys out to a .reg file then you can run this in your loginscript:
regedit /s regfile.reg
The /s is an undocumented command that means silent, the user wont be prompted that something was updated in the registry.
A lazy sysadmin is a good sysadmin!
Neither the WSUS server or the client machines require domain membership to communicate.