Mysql won't start - ibdata1 corrupt? - operating system error number 13 - permissions issue

Question

Server shutdown from power failure.
Mysql will not start now.
Disk is not full. Syslog is below

Oct 11 15:03:31 joe mysqld_safe[24757]: started
Oct 1         


        

Answer 1

In short, (especially on RHEL/CentOS/Fedora) try

getenforce

if it replies with Enforcing you have SELinux up and running. Temporarily deactivate it with setenforce 0 and see if MariaDB starts now! Rather common, especially on RHEL/CentOS/Fedora.

There's more about this further down, as well as in this official article.

In general

There are more things in a UNIX environment that might prevent file access, than just user access rights.

• Security modules like SELinux (see above) or AppArmor (as Dan mentioned) could disallow it
• Access Control Lists (ACL) could be specifically set, for the required files/directories
• Any of the parent folders could be owned by another user, and have no x (="dir access") set for others

Additionally there could be other unexpected factors, like ...

• The mysql datadir being set to a place, where mysql doesn't have permissions (see /etc/my.cnf)
• Mysql could (strangely) be running as a different user, or the file could be simply owned by someone else

Just to mention a view things off the top of my head (feel free to edit/add to this answer btw).

In the case, SELinux is "the problem"

For a permanent solution, you could try to restore the appropriate security context, ...

restorecon -R /var/lib/mysql/

... or just deactivate SELinux (but think about this one a little bit before doing so), by editing the config (typically in /etc/selinux/config) and setting SELINUX=disabled as suggested in following article.

• Here the official help page from mariadb.com: What to do if MariaDB doesn't start
• And here something from redhat.com: MariaDB Changing Database Location

Obviously those are applicable to MySQL just the same way.