mysql可以启动，但是不定时会发现网址无法访问，提示就是建立数据库时出错，求大神帮助！
启动mysql时会报以下错误：
2015-08-27 1758 27754 [Note] Plugin 'FEDERATED' is disabled.
2015-08-27 1758 27754 [ERROR] Function 'innodb' already exists
2015-08-27 1758 27754 [Warning] Couldn't load plugin named 'innodb' with soname 'ha_innodb.so'.
2015-08-27 1758 27754 [ERROR] Function 'federated' already exists
2015-08-27 1758 27754 [Warning] Couldn't load plugin named 'federated' with soname 'ha_federated.so'.
2015-08-27 1758 27754 [ERROR] Function 'blackhole' already exists
2015-08-27 1758 27754 [Warning] Couldn't load plugin named 'blackhole' with soname 'ha_blackhole.so'.
2015-08-27 1758 27754 [ERROR] Function 'archive' already exists
2015-08-27 1758 27754 [Warning] Couldn't load plugin named 'archive' with soname 'ha_archive.so'.
2015-08-27 1758 27754 [Note] InnoDB: Using atomics to ref count buffer pool pages
2015-08-27 1758 27754 [Note] InnoDB: The InnoDB memory heap is disabled
2015-08-27 1758 27754 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
2015-08-27 1758 27754 [Note] InnoDB: GCC builtin _atomicthread_fence() is used for memory barrier
2015-08-27 1758 27754 [Note] InnoDB: Compressed tables use zlib 1.2.8
2015-08-27 1758 27754 [Note] InnoDB: Using Linux native AIO
2015-08-27 1758 27754 [Note] InnoDB: Not using CPU crc32 instructions
2015-08-27 1758 27754 [Note] InnoDB: Initializing buffer pool, size = 128.0M
2015-08-27 1759 27754 [Note] InnoDB: Completed initialization of buffer pool
2015-08-27 1759 27754 [Note] InnoDB: Highest supported file format is Barracuda.
2015-08-27 1759 27754 [Note] InnoDB: 128 rollback segment(s) are active.
2015-08-27 1759 27754 [Note] InnoDB: 5.6.25 started; log sequence number 50792916
2015-08-27 1759 27754 [Note] Server hostname (bind-address): '127.0.0.1'; port: 3306
2015-08-27 1759 27754 [Note] - '127.0.0.1' resolves to '127.0.0.1';
2015-08-27 1759 27754 [Note] Server socket created on IP: '127.0.0.1'.
2015-08-27 1759 27754 [Note] Event Scheduler: Loaded 0 events
2015-08-27 1759 27754 [Note] /usr/sbin/mysqld: ready for connections.
Version: '5.6.25-3' socket: '/var/run/mysqld/mysqld.sock' port: 3306 (Debian)
http://blog.csdn.net/chszs/article/details/49469819
MySQL 5.6服务器初始化脚本添加了以下的插件表，而实际上MySQL 5.6不依赖于任何插件。
mysql> select * from mysql.plugin;
| name | dl |
| innodb | ha_innodb.so |
| federated | ha_federated.so |
| blackhole | ha_blackhole.so |
| archive | ha_archive.so |
4 rows in set (0.00 sec)
解决它很简单，执行命令：
mysql> delete from mysql.plugin;
Query OK, 4 rows affected (0.00 sec)