[Infrastructures] authentication of groups of users

[Rudy Gevaert]

Hello,

How does one easily setup systems that allow only some people to
login?

E.g. the on the main servers only a couple of people are allowed to
login.

When using NIS (as a directory server and authentication server) this
can be acomplished adding the relevant + en - entries in the passwd
file and using NIS domains (however keeping all in one NIS domain is
preferable).

But what with using LDAP as directory server and authentication
server? What can you do to accomplish the same effect?  

And what with Kerberos (and a directory server of your choice)?

What are some ways to do this?

Thank you in advance,

Rudy