[MySQL错误]Can't find file: ./mysql/plugin.frm

错误提示：

/usr/libexec/mysqld: Can't find file: './mysql/plugin.frm' (errno: 13)
180530 15:19:43 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.

版本环境：

mysql> select version();
+------------+
| version()  |
+------------+
| 5.1.73-log |
+------------+

做主从复制时，把主库的mysql整个目录都复制到了备库的目录下，启动服务失败，查看日志，出现这个错误：

#vim /var/log/mysqld.log
/usr/libexec/mysqld: Can't find file: './mysql/plugin.frm' (errno: 13)
180530 15:19:43 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.

到mysql目录中，发现plugin.frm文件是存在的，权限也是mysql

google了一下，发现是因为开启了SELinux造成的，关闭SELinux即可正常启动MySQL

关闭SELinux:

临时关闭： #setenforce 0

永久关闭：

#vim /etc/sysconfig/selinux
SELINUX=disabled