You don’t exist, go away!

[email protected]:~> ssh localhost -lroot
You don’t exist, go away!
[email protected]:~>

A paradoxical existential critic of your solipsistic non-existence is probably not what you want to be greeted with when attempting to administrate your box. The error actually means the system can’t lookup your userid. Which means your usernumber say 500 can’t be resolved to your username say: cpugwash.

Possible causes are:

Your user has been deleted from the /etc/passwd file.
Your user has been deleted from another authentication system you use, like LDAP.
Your LDAP or other authentication server is not running.

In my case, LDAP had crashed and needed restarting.

Some random rambling on this topic here.