Ubuntu 11.10 mysql problem after upgrade

原文网址：http://my.opera.com/djfake/blog/2011/11/05/ubuntu-11-10-mysql-problem-after-upgrade

Ubuntu 11.10 mysql problem after upgrade

Saturday, November 5, 2011 12:35:18 AM

mysql, Ubuntu, apparmor, mysqld, 11.10, upgrade

If you find that mysql doesn't run after upgrading to 11.10, it could an issue with the fact that /var/run was replaced with /run.

Check  /var/log/mysql/error.log, and you'll find something like this: 

111104 19:11:33 [Note] Plugin 'FEDERATED' is disabled.
111104 19:11:33  InnoDB: Initializing buffer pool, size = 8.0M
111104 19:11:33  InnoDB: Completed initialization of buffer pool
111104 19:11:34  InnoDB: Started; log sequence number 0 44233
111104 19:11:34 [ERROR] Can't start server : Bind on unix socket: Permission den
ied
111104 19:11:34 [ERROR] Do you already have another mysqld server running on soc
ket: /var/run/mysqld/mysqld.sock ?
111104 19:11:34 [ERROR] Aborting

Or if you try to login to mysql, you'll get this:

ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)

Well, here's the fix! Go edit  /etc/apparmor.d/usr.sbin.mysqld as root and replace

  /var/run/mysqld/mysqld.pid w,
  /var/run/mysqld/mysqld.sock w,

with 

  /{,var/}run/mysqld/mysqld.pid w,
  /{,var/}run/mysqld/mysqld.sock w,

then 

sudo service mysql restart

and viola! our mysql db's are back!