Please Note: The problem I describe below seems to have "gone away" on its own. But that's not very comforting, so I'm hoping for a solution, or at least an explanation, should it recur.
I was just preparing a Slicehost virtual server for a LAMP role, using the Ubuntu Lucid server (CLI-only). I created an account for myself (yukondude) but was doing most of the installations as root. At some point in the process, the mysql-server package (
aptitude install -Pr mysql-server) failed with this error:
Unable to set password for the MySQL "root" user An error occurred while setting the password for the MySQL administrative user. This may have happened because the account already has a password, or because of a communication problem with the MySQL server.
This was the first time mysql-server had been installed, so the problem couldn't have been a previous password. The installation script then dumped these lines to the terminal:
100903 19:57:05 [Note] Plugin 'FEDERATED' is disabled. /usr/sbin/mysqld: Can't create/write to file '/tmp/iblv4tJ0' (Errcode: 13) 100903 19:57:05 InnoDB: Error: unable to create temporary file; errno: 13 100903 19:57:05 [ERROR] Plugin 'InnoDB' init function returned error. 100903 19:57:05 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed. ERROR: 1146 Table 'mysql.user' doesn't exist 100903 19:57:05 [ERROR] Aborting
It hung at this point, so I manually killed the installation processes.
I then discovered that the Apache2 server was refusing to serve my test index.html file, instead producing a 403 Forbidden message, even though the permissions for /var/www/index.html were wide open and the Apache config hadn't changed. I was also unable to log in through SSH to my yukondude account, and the command
su - yukondude produced a
cd /home/yukondude Permission Denied error (I'm afraid I don't have a copy of the exact error message). The permissions and ownership for /home/ and /home/yukondude/ were perfectly normal. Looking back at the mysql-server errors, I wondered if the access to the file in /tmp/ was related.
What could've caused this bizarre permissions problem? I've never seen anything like it before. I wondered whether PAM might be involved, but I don't know that system as well as I should. I'm not sure whether the mysql-server install was really the culprit, or just a victim of the permissions problem that cropped up at that moment.
I tried a complete re-install from a fresh image with the exact same result. My third and final attempt did work (the difference was that I updated my package versions before any installations), so I appear to be in the clear this morning. But I'm nervous that the same problem might someday re-occur. I tried Googling for help, but haven't figured out a good search phrase. Any suggestions?
Update: I'm going to start a bounty. As I pointed out, this problem isn't affecting me anymore, but I sure would like to have an inkling of what happened. I'd also appreciate comments from anyone who's experienced something similar in case those circumstances provide clues.