service mysqld start 报错
090517 13:34:15 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
090517 13:34:15 [ERROR] Fatal error: Can't open and lock privilege tables: Table 'mysql.host' doesn't exist
090517 13:34:15 mysqld_safe mysqld from pid file /usr/local/mysql/var/mail.bmitwap.com.pid ended
090517 13:38:35 mysqld_safe Starting mysqld daemon with databases from /usr/local/mysql/data
解决办法：
在运行初始化权限表的时候使用增加参数--datadir ，命令格式为：
shell> ./scripts/mysql_install_db --user=mysql --datadir=/usr/local/mysql/data
这样问题就解决了。