ERROR 2002 (HY000): Can't connect server socket /tmp/mysql.sock

自己採用的解決方案：
啟動MySQL資料庫：


***@***-VirtualBox:~$ sudo /etc/init.d/mysql.server start
Starting MySQL
.... * The server quit without updating PID file (/usr/local/mysql/data/***-VirtualBox.pid).

針對以上錯誤，網上各種百度，各種谷歌都解決不了，還是提示上面的同樣的錯誤


我採用下面的方法，竟然可以啟動MySQL，但是又引發了其他的無法解決的error
##################################    方法如下    ##############################
按照網址：http://www.justin.my/2012/03/starting-mysql-error-the-server-quit-without-updating-pid-file/
竟然可以啟動MySQL服務，如下：
***@***-VirtualBox:/etc$ sudo mv /etc/my.cnf /etc/my.cnf.old
***@***-VirtualBox:/etc$ sudo /etc/init.d/mysql.server start
Starting MySQL
.. * 

但是，無法登陸了：
***@***-VirtualBox:/etc/mysql/conf.d$ sudo mysql -u root -p
Enter password: 
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)


這個錯誤我用了各種辦法無法解決，無奈把my.cnf的名稱變回來：

***@***-VirtualBox:/etc$ sudo mv /etc/my.cnf.old  /etc/my.cnf
####################################################################

解決方法：

檢視錯誤日誌，定位到日誌最後幾行：***@***-VirtualBox:/usr/local/mysql$ more ./data/***-VirtualBox.err

 

##### 日誌內容  start #####

140928 08:52:32 mysqld_safe mysqld from pid file /usr/local/mysql/data/ga

oyu-VirtualBox.pid ended

140928 10:53:01 mysqld_safe Starting mysqld daemon with databases from /u

sr/local/mysql/data

140928 10:53:01 [Note] Plugin 'FEDERATED' is disabled.

140928 10:53:01 InnoDB: The InnoDB memory heap is disabled

140928 10:53:01 InnoDB: Mutexes and rw_locks use InnoDB's own implementat

ion

140928 10:53:01 InnoDB: Compressed tables use zlib 1.2.3

140928 10:53:01 InnoDB: Using Linux native AIO

140928 10:53:01 InnoDB: Initializing buffer pool, size = 128.0M

140928 10:53:01 InnoDB: Completed initialization of buffer pool

140928 10:53:01 InnoDB: highest supported file format is Barracuda.

140928 10:53:01  InnoDB: Waiting for the background threads to start

140928 10:53:02 InnoDB: 5.5.39 started; log sequence number 44664632

140928 10:53:02 [ERROR] /usr/local/mysql/bin/mysqld: unknown variable 'de

fault-character-set=utf8'

140928 10:53:02 [ERROR] Aborting

140928 10:53:02  InnoDB: Starting shutdown...

140928 10:53:03  InnoDB: Shutdown completed; log sequence number 44664632

140928 10:53:03 [Note] /usr/local/mysql/bin/mysqld: Shutdown complete

140928 10:53:03 mysqld_safe mysqld from pid file /usr/local/mysql/data/ga

oyu-VirtualBox.pid ended

 

##### 日誌內容  end #####   

 

 

記得自己為了解決同事的字元編碼問題，把自己機器上面的配置檔案修改過：修改了/etc/my.cnf裡面的【mysqld】的字元設定，在修改回來，試試看，修改方法如下：

把 [client] [mysqld] [mysql]裡面的  default-character-set=utf8 都註釋掉

發現好使了，可以成功登陸MySQL了。

***@***-VirtualBox:/usr/local/mysql$ sudo /etc/init.d/mysql.server start

Starting MySQL

.... * 

***@***-VirtualBox:/usr/local/mysql$ sudo mysql -u root -p

Enter password: 

Welcome to the MySQL monitor.  Commands end with ; or \g.

Your MySQL connection id is 1

Server version: 5.5.39-log MySQL Community Server (GPL)

 

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