Solve centos server exception power-off mysql startup exception Mysql startup error: mysqld

Solve centos server exception power-off mysql startup exception Mysql startup error: mysqld

Symptom:
Centos server exception power-off MySQL startup exception Mysql startup error: mysqld_safe mysqld from pid file/usr/local/mysql/Linux. pid end
But open the log file to view

InnoDB: Completed initialization of buffer pool
InnoDB: Error: log file./ib_logfile0 is of different size 50331648 bytes
InnoDB: than specified in the. cnf file 5242880 bytes!
160603
[ERROR] Plugin 'innodb' init function returned error.
160603
14:06:15 [ERROR] Plugin 'innodb' registry as a storage engine failed.
160603
At 14:06:15 [ERROR] Unknown/unsupported storage engine: InnoDB
160603 14:06:15 [ERROR] Aborting

Solution:

1. Storage engine error
Unknown/unsupported storage engine: InnoDB
2. Check the innodb parameter in the configuration file. If skip-innodb has been commented out
3. If innodb_log_file_size is reset,
4. delete several rm-rf ib_logfiles and restart the database.