.根据配置，怎么mysql启动不了

描述：[liu@localhost Desktop]$ ll /data/server/
total 4
drwxrwxrwx. 5 mysql mysql 4096 Apr 27 05:01 mysql
 
[liu@localhost Desktop]$ sudo /opt/Percona-Server-5.5.21-rel25.0/bin/mysqld_safe --defaults-file=/opt/Percona-Server-5.5.21-rel25.0/my.cnf
130427 06:45:55 mysqld_safe Logging to '/opt/Percona-Server-5.5.21-rel25.0/data/localhost.localdomain.err'.
130427 06:45:55 mysqld_safe Starting mysqld daemon with databases from /opt/Percona-Server-5.5.21-rel25.0/data
130427 06:45:55 mysqld_safe mysqld from pid file /opt/Percona-Server-5.5.21-rel25.0/data/localhost.localdomain.pid ended

[liu@localhost Desktop]$ sudo vim /opt/Percona-Server-5.5.21-rel25.0/data/localhost.localdomain.err
查看结果安装配置方面没有问题

解决：根据echo "  方法3： ${mysql_path}/bin/mysqld_safe --defaults-file=${mysql_path}/my.cnf --datadir=${mysql_data_path} &"
运行：sudo /opt/Percona-Server-5.5.21-rel25.0/bin/mysqld_safe --defaults-file=/opt/Percona-Server-5.5.21-rel25.0/my.cnf --datadir=/data/server/mysql/

然后，mysql就可以执行了