service mysql start出錯，mysql啟動不了，解決mysql: unrecognized service錯誤的方法如下：
[root@ctohome.com ~]# service mysql start
mysql: unrecognized service
[root@ctohome.com ~]# service mysql restart
mysql: unrecognized service
[root@ctohome.com ~]# rpm -q mysql 查詢發現mysql已經正常安裝
mysql-5.1.52-jason.1
[root@ctohome.com ~]# /etc/rc.d/init.d/mysqld start 直接啟動沒問題
Starting mysqld: [ OK ]
[root@ctohome.com ~]# ls /etc/rc.d/init.d/mysqld -l
-rwxr-xr-x 1 root root 5509 Dec 18 02:31 /etc/rc.d/init.d/mysqld
[root@ctohome.com ~]# chkconfig mysqld on 設定mysql開機啟動
[root@ctohome.com ~]# chmod 755 /etc/rc.d/init.d/mysqld 修改mysqld執行許可權
[root@ctohome.com ~]# service mysqld start 搞定
Starting mysqld: [ OK ]
[root@ctohome.com ~]# service mysqld start
Starting mysqld: [ OK ]
[root@ctohome.com ~]# service mysqld status
mysqld (pid 9487) is running...