启动mysql时报错：
141220 07:50:59 mysqld_safe mysqld from pid file /usr/local/mysql/data/.pid ended
141220 07:54:30 mysqld_safe Starting mysqld daemon with databases from /usr/local/mysql/data
141220 7:54:30 [Note] Plugin ‘InnoDB’ is disabled.
141220 7:54:30 [Note] Server hostname (bind-address): ‘0.0.0.0’; port: 3306
141220 7:54:30 [Note] – ‘0.0.0.0’ resolves to ‘0.0.0.0’;
141220 7:54:30 [Note] Server socket created on IP: ‘0.0.0.0’.
141220 7:54:30 [Note] Event Scheduler: Loaded 0 events
141220 7:54:30 [Note] /usr/local/mysql/bin/mysqld: ready for connections.
Version: ‘5.5.34-log’ socket: ‘/tmp/mysql.sock’ port: 3306 Source distribution
141220 7:54:48 [Note] /usr/local/mysql/bin/mysqld: Normal shutdown
分析：是/tmp/mysql.sock 不存在
由于mysql 默认的mysql.sock 是在/var/lib/mysql/mysql.sock，创建符号连接：
ln -s /var/lib/mysql/mysql.sock /tmp/mysql.sock
然后启动mysql，搞定
