In the login.defs file there is a switch to disable logins for users by
putting NOLOGIN in the shell field in the /etc/passwd file. This is
supposed to disable logins but still allow "su". When I do a "usermod -s
NOLOGIN testuser" and try to login under testuser I get an error that it
can't execute NOLOGIN : No such file or directory. When I try to su -
testuser I get the same error and don't get logged in as that user. Can
anyone help me with this.