While logged in as
root I would like to
su to a specific regular user. I run
su username and immediately receive the prompt back, still as root. There is no error given. I'm aware of the old "the user you're trying to su to doesn't have permission for the folder you're currently in" problem, and that's not the case in this scenario. Furthermore, there is no error displayed, which is always the case (as far as I know) when that particular permissions issue is encountered.
su - username with the same effect. The command is processed, no errors are seen, and I receive the prompt back immediately.
What could be causing this behavior? How can I troubleshoot this?