Deny LDAP user...

Hello!

I'm using OpenLDAP for authentication. How do I deny an ldap user
authenticating on a specific workstation?

For example, I have 3 computers configured to use ldap authentication -
2 are workstations, 1 is a server. I only want users belonging to the
Admins Group to have permission to log on to the server.

Any ideas?

Thanks,
Mike