面板5.9中MYSQL无法启动求助

ERROR! MySQL server PID file could not be found!
Starting MySQL... ERROR! The server quit without updating PID file (/www/server/data/localhost.localdomain.pid).
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180717 13:26:48 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
180717 13:26:50 [ERROR] Aborting
180717 13:26:51 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
180717 13:26:53 [ERROR] Aborting
180717 13:26:56 [ERROR] Aborting
180717 13:27:03 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
180717 13:27:04 [ERROR] Aborting
180717 13:34:39 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
180717 13:34:40 [ERROR] Aborting
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mysql start error.
mysql无法正常启动，请将以上错误信息截图发至论坛寻求帮助
[root@localhost ~]#