mysql 两种链接方式：socket和TCP/IP

参考mysql 链接方式：socket和tcp/ip

unix系统上，mysql的登录方式有两种，分别是socket和tcp/ip方式登录。

当server和client在同一台服务器上的时候，咱们能够直接用mysql命令登录。

[root@mysql ~]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.5.46-log MySQL Community Server (GPL)

Copyright (c) 2000, 2015, 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.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

root@[(none)]>

当什么参数都没有指定的时候，mysql默认使用socket方式登录，若是my.cnf的[client]没有指定socket文件路径时，mysql默认会去寻找/tmp/mysql.sock，因此若是mysql服务启动的时候，生成的socket文件不是默认路径的话，登录会报错。

[root@mysql ~]# mysql
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)

mysql服务启动的时候，socket文件的生成目录能够在[mysqld]上指定，若是没有指定，默认是/tmp/mysql.sock；

mysql登录的时候，指定参数-h，会使用tcp/ip的方式链接，若是没有指定端口的话，默认是使用3306端口

[root@mysql ~]# mysql -h192.1.1.20
ERROR 2003 (HY000): Can't connect to MySQL server on '192.1.1.20' (111)

[root@mysql ~]# mysql -h192.1.1.20 -P3307
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.5.46-log MySQL Community Server (GPL)

Copyright (c) 2000, 2015, 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.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

root@[(none)]>

当mysql登录时，同时指定-h和-S，mysql会默认使用tcp/ip的方式链接。

[root@mysql ~]# mysql -h192.1.1.20 -P3307  -S /ddd/sdfs.scok
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.5.46-log MySQL Community Server (GPL)

Copyright (c) 2000, 2015, 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.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

root@[(none)]>

随便指定一个socket文件均可以登录。

 

能够查看简洁版的：MySQL 链接方式

更多细节能够查看 ：http://blog.itpub.net/15480802/viewspace-1755100/