centos下mysql安装启动报错"mysql deamon failed to start"错误的解决方法

1. 执行 start报错：

# /etc/init.d/mysqld start 
MySQL Daemon failed to start. 
Starting mysqld: [FAILED] 

 2. 查看mysqld的log文件 

#tail -n 100 /var/log/mysqld.log 

[ERROR] InnoDB: The Auto-extending innodb_system data file './ibdata1' is of a different size 640 pages (rounded down to MB) than specified in the .cnf file: initial 768 pages, max 0 (relevant if non-zero) pages!
[ERROR] InnoDB: Plugin initialization aborted with error Generic error
[ERROR] Plugin 'InnoDB' init function returned error.
[ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
[ERROR] Failed to initialize plugins.
[ERROR] Aborting

3. 解决方法：

由于是初次安装报错，直接删除/var/lib/mysql目录下的所有文件，然后重启即成功。