I've an LPAR set up on a P690. The LPAR ran AIX v5.2. I then did an upgrade (using the migration option) to AIX v5.3. I've now encountered the problem that, at the console, I cannot log in as root (or as anyone else that matter). I get the login prompt, enter "root " and then the shell returns to the login prompt.
I get the same result if I enter any other defined user name. If I enter a non-existing name, then the shel prompts for a password and then returns the unkown user/password error.
I've tried going via maintenance mode and using the "passwd" command to reset root's password but this did not work.
Any suggestions?