如果你的webmin/virtualmin自动备份出现下面的错误，那么，就是mysql升级后没有做mysql_upgrade 表修复。 在新版下执行mysql_upgrade命令，其实这个命令包含一下三个命令：

# mysqlcheck –check-upgrade –all-databases –auto-repai

# mysql_fix_privilege_tables

# mysqlcheck –all-databases –check-upgrade –fix-db-names –fix-table-names

Note: 在每一次的升级过程中，mysql_upgrade这个命令我们都应该去执行，它通过mysqlcheck命令帮我们去检查表是否兼容新版本的数据库同时作出修复，还有个很重要的作用就是使用mysql_fix_privilege_tables命令去升级权限表。

升级mysql的详细方法： Centos5.4(webmin)中Yum升级mysql5.1和php5.2(禁止php5.3)

Creating backup for virtual server ..
Copying virtual server configuration .. .. done
Copying Apache virtual host configuration .. .. done
Copying Apache log files .. .. done
Copying Logrotate configuration .. .. done
Dumping MySQL database pmxujun .. .. dump failed! mysqldump: Couldn't execute 'SHOW FUNCTION STATUS WHERE Db = 'pmxujun'': Column count of mysql.proc is wrong. Expected 20, found 16. Created with MySQL 50077, now running 50152. Please use mysql_upgrade to fix this error. (1558)
Creating TAR file of home directory .. .. done