操作系统：Ubuntu 11.10

MySQL版本：5.1

症状：重启服务器后，MySQL无法启动，执行sudo service mysql start花费很长时间，无错误提示。

解决：

1）查看日志：sudo cat /var/log/mysql/error.log，大致如下：

qi@site-digger:/var/log/mysql# sudo cat /var/log/mysql/error.log 
130216 16:11:32 [Note] Plugin 'FEDERATED' is disabled.
130216 16:11:32  InnoDB: Initializing buffer pool, size = 8.0M
130216 16:11:32  InnoDB: Completed initialization of buffer pool
130216 16:11:33  InnoDB: Started; log sequence number 0 1382359817
130216 16:11:33 [ERROR] Can't start server: Bind on TCP/IP port: Cannot assign requested address
130216 16:11:33 [ERROR] Do you already have another mysqld server running on port: 3306 ?
130216 16:11:33 [ERROR] Aborting

130216 16:11:33  InnoDB: Starting shutdown...
130216 16:11:38  InnoDB: Shutdown completed; log sequence number 0 1382359817
130216 16:11:38 [Note] /usr/sbin/mysqld: Shutdown complete

日志给出的原因是：可能3306端口被其它程序占用的。真是如此吗？

2）查看谁占了3306。执行sudo netstat -nat | grep 3306，但是无结果返回，说明并非是由于端口被占用了。

3）那到底是怎么回事呢？？？在stackovflow上发帖询问，有高人指点让查看下my.conf里的bind-address参数，查看其值为127.0.0.1。貌似也没啥问题。很困惑...

4）无意识地敲了个ifconfig，显示结果如下。顿时灵机一动，额滴神啊，谁把127.0.0.1改成127.0.0.2了？？问题找到了。

qi@site-digger:~$ ifconfig
venet0    Link encap:UNSPEC  HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00  
          inet addr:127.0.0.2  P-t-P:127.0.0.2  Bcast:0.0.0.0  Mask:255.255.255.255
          UP BROADCAST POINTOPOINT RUNNING NOARP  MTU:1500  Metric:1
          RX packets:6072143 errors:0 dropped:0 overruns:0 frame:0
          TX packets:7166117 errors:0 dropped:523 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:4602064461 (4.6 GB)  TX bytes:7104219611 (7.1 GB)

venet0:0  Link encap:UNSPEC  HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00  
          inet addr:199.167.132.58  P-t-P:199.167.132.58  Bcast:0.0.0.0  Mask:255.255.255.255
          UP BROADCAST POINTOPOINT RUNNING NOARP  MTU:1500  Metric:1

5）编辑/etc/network/interfaces，将127.0.0.2改回127.0.0.1，并执行sudo /etc/init.d/networking restart。然后再sudo service mysql restart，哦了！