mysql启动失败“MySQL Daemon failed to start”

CentOS上，用命令：service mysqld restart 启动mysql报错：

# service mysqld restart
Stopping mysqld:                                           [  OK  ]
MySQL Daemon failed to start.
Starting mysqld:                                           [FAILED]

进入mysql相关目录查看：

# cd /var/lib/mysql/
# ls
hhw_global  ibdata1  ib_logfile0  ib_logfile1  localhost.localdomain.err  mysql  mysql.sock  test

查看服务器启动日志：

# tail localhost.localdomain.err
 :: mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql
 :: [ERROR] You need to use --log-bin to make --binlog-format work.
 :: [ERROR] Aborting

 :: [Note] /usr/libexec/mysqld: Shutdown complete

 :: mysqld_safe mysqld from pid file /var/run/mysqld/mysqld.pid ended

可用看到，两行报错说的是，开了--binlog-format选项却没有开启bin log，因此mysql进程开不起来。使用如下命令，查看一下配置的位置：

# mysqld --verbose --help|grep -A  'Default options'

或者是：

# mysql --verbose --help|grep -A  'Default options'

查询结果：

# mysql --verbose --help|grep -A  'Default options'
Default options are read from the following files in the given order:
/etc/mysql/my.cnf /etc/my.cnf ~/.my.cnf 

找到相应的my.cnf，修改相应配置项，重启mysqld服务即可。