180720 10:00:54 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
180720 10:00:54  InnoDB: Initializing buffer pool, size = 8.0M
180720 10:00:54  InnoDB: Completed initialization of buffer pool
InnoDB: Error: log file ./ib_logfile0 is of different size 0 5242881 bytes
InnoDB: than specified in the .cnf file 0 5242880 bytes!
180720 10:00:54 [ERROR] Plugin 'InnoDB' init function returned error.
180720 10:00:54 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
180720 10:00:54 [ERROR] Fatal error: Can't open and lock privilege tables: Table 'mysql.host' 

1.解决：mysql_install_db --user=mysql --basedir=/usr/ --ldata=/var/lib/mysql/

2.查看分析错误

vim /var/lib/mysql/instance-ggicik0l.err