log in problem

[dandan123]

I'm having problems with an account used to scan servers.

It fails only on one server, it's able to log in using ssh and a public key and then gets logged off immediately.

Any idea how to go about troubleshooting ?

It's using ksh and that works ok, ksh is in /etc/shells file.

 

[dandan123]

Someone had put in a /etc/nologin file..

 

[sbrews]

can you get in with any other account? If not, then like dandan123 said - someone put in a /etc/nologin file. If so, then perhaps somone set up that account so that its profile executes an exit/logout command.

If it is /etc/nologin, log in - as root on the console - and remove the file. Otherwise you need to figure out who/why the account was "disabled".