Summary

We stated that a Linux login attempt can fail for many reasons. The information provided in this chapter should enable the reader to troubleshoot login problems more effectively:

• If a user can't log in, use chage to see whether login for the account is disabled due to password aging settings.

• If login only fails for the root user, try logging in as a normal user and using su to switch to root because /etc/securetty might exist but contain no devices.

• If at least one user can log in, the global login restriction file /etc/nologin is not the trouble. If all users are having login problems, check for /etc/nologin and look for PAM module problems.

• If you are still having problems, you could try creating a new user with the default dot configuration files to verify that customization of .bash_profile or some other dot file is not preventing successful logins.