[Samba] deny file access or specific users

[mj]

Hi,

For some users I am trying to deny file access to our domain member 
servers, yet keeping their AD account for all other purposes, like email 
and ldap authorized clients.

So I figured I removed the unix attributes from a user in ADUC, while 
keeping the rest. I expected that would make the user 'invisible' for 
the domain member (file) servers, while maintaining the account for 
everything else.

Now, a day later, on one our domain member servers the user is gone:

> root at server1:~# wbinfo -u | grep test
> test
> root at server1:~# id test
> id: ‘test’: no such user
> root at server1:~# getent passwd test
> root at server1:~# 

but on another server, the user still remains

> root at server2:~# wbinfo -u | grep test
> test
> root at server2:~# id test
> uid=63993(test) gid=513(domain users) groups=513(domain users),1000001(BUILTIN\users)
> root at server2:~# getent passwd test
> test:*:63993:513::/home/WRKGRP/test:/bin/false
> root at server2:~# 

Probably running net cache flush will remove the user on server2 as 
well, but is there an expiration on the winbind cache? Will the user 
disppear from server2 automatically after a certain period?

Otherwise we have to perform the additional manual flush of the net 
cache on each domain member server, each time we want to deny fileserver 
access for a user.

Or is there a better way to keeping everything, while centrally denying 
fileserver access for specific users?

MJ