linux+mysql安装配置问题

【问题】

080825 9:38:04 [ERROR] Can't start server : Bind on unix socket: Permission denied
080825 9:38:04 [ERROR] Do you already have another mysqld server running on socket: /var/lib/mysql/mysql.sock ?

mysql.sock 是启动mysql时自动生成。在/etc/my.cnf文件中配置mysql.sock文件的存放位置。

Mysql客户端和服务器端在本机的通信方式，是通过一个名为mysql.sock 文件来进行初始化通信的。

所以在my.cnf 中client端和server端的sock配置应该一致，否则会出现该问题。

[client]

#password       = your_password
port            = 3306
#socket         = /var/lib/mysql/mysql.sock
socket          = /usr/local/mysql/data/mysql.sock

[mysqld]
port            = 3306
#socket         = /var/lib/mysql/mysql.sock
socket          = /usr/local/mysql/data/mysql.sock

【几个说明】

1. 安装mysql时，建议指定安装目录为/usr/local/mysql , 否则默认安装目录为 /usr/bin, 包括mysql，mysqld等启动文件

my.cnf 文件中如果没有配置datadir，则默认目录是/var/lib/mysql。修改配置文件datadir =/usr/local/mysql/data

2. 注意 /usr/local/mysql/data 的权限问题， chown -R mysql:mysql data/

drwxr-xr-x 5 mysql mysql     4096 Jun 11 22:19 data

3. 查看3306的端口是否被监听 netstat -tunpl | grep 3306

[root@host data]# netstat -tunpl | grep 3306
tcp        0      0 0.0.0.0:3306                0.0.0.0:*                   LISTEN      22926/mysqld     

4. 查找文件和目录所在位置 find / -name "*mysql*" -print

[root@host data]# find / -name "*mysql*" -print
/home/mysql
/var/spool/mail/mysql
/var/lock/subsys/mysql
/var/lib/mysql
/var/lib/mysql/mysql-bin.000003
/var/lib/mysql/mysql-bin.000002
/usr/local/mysql
/usr/local/mysql/data/mysql
/usr/local/mysql/data/mysql.sock

5. [root@host bin]#mysqladmin version
mysqladmin  Ver 8.42 Distrib 5.5.25, for Linux on x86_64
Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.


Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.


Server version          5.5.25-log
Protocol version        10
Connection              Localhost via UNIX socket
UNIX socket             /usr/local/mysql/data/mysql.sock
Uptime:                 24 min 13 sec


Threads: 1  Questions: 1  Slow queries: 0  Opens: 33  Flush tables: 1  Open tables: 26  Queries per second avg: 0.000

6. PLEASE REMEMBER TO SET A PASSWORD FOR THE MySQL root USER !
To do so, start the server, then issue the following commands:

/usr/bin/mysqladmin -u root password 'new-password'
/usr/bin/mysqladmin -u root -h BJCSI-NBG-DBU password 'new-password'