I have a special lab machine (linux) and two different users will be using this machine. They need to log in with the same userid. I want to prevent both of them from logging in at the same time. How can I do that?
I was thinking of starting with something simple like this - Use the users source IP-address and add some checks in
If a user logs in from IPAddress1 and there is already somebody ssh'ed in from IPAddress2 then print a big fat message.