MySQL修改数据目录后无法启动

Ubuntu 9.10 有个apparmor.
my.cnf里面有段注释

[mysqld]
#
# * Basic Settings
#
#
# * IMPORTANT
# If you make changes to these settings and your system uses apparmor, you may
# also need to also adjust /etc/apparmor.d/usr.sbin.mysqld.
#

查看/etc/apparmor.d/usr.sbin.mysqld, 的确是一些目录的权限设置. 把/var/lib/mysql 改成 /data/mysql.

# /etc/init.d/apparmor restart

在启动mysql就可以成功了