2016-09-14T09:17:37.713955Z 0 [Note] InnoDB: If the mysqld execution user is authorized, page cleaner thread priority can be changed. See the man page of setpriority().
2016-09-14T09:17:37.724151Z 0 [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!
2016-09-14T09:17:37.724165Z 0 [ERROR] InnoDB: Plugin initialization aborted with error Generic error
2016-09-14T09:17:38.347878Z 0 [ERROR] Plugin 'InnoDB' init function returned error.
2016-09-14T09:17:38.347902Z 0 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
2016-09-14T09:17:38.347906Z 0 [ERROR] Failed to initialize plugins.
2016-09-14T09:17:38.347913Z 0 [ERROR] Aborting
To solve this problem add the below given line in /etc/my.cnf file inside [mysqld] block.
innodb_data_file_path = ibdata1:10M:autoextend
service mysqld restart
restorecon -R /var/lib/mysql/chmod -R 777 /var/lib/mysql