mysql 兩種鏈接方式：socket和TCP/IP

參考mysql 鏈接方式：socket和tcp/ip

unix系統上，mysql的登錄方式有兩種，分別是socket和tcp/ip方式登錄。

當server和client在同一臺服務器上的時候，咱們能夠直接用mysql命令登錄。

[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)]>

當什麼參數都沒有指定的時候，mysql默認使用socket方式登錄，若是my.cnf的[client]沒有指定socket文件路徑時，mysql默認會去尋找/tmp/mysql.sock，因此若是mysql服務啓動的時候，生成的socket文件不是默認路徑的話，登錄會報錯。

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

mysql服務啓動的時候，socket文件的生成目錄能夠在[mysqld]上指定，若是沒有指定，默認是/tmp/mysql.sock；

mysql登錄的時候，指定參數-h，會使用tcp/ip的方式鏈接，若是沒有指定端口的話，默認是使用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)]>

當mysql登錄時，同時指定-h和-S，mysql會默認使用tcp/ip的方式鏈接。

[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)]>

隨便指定一個socket文件均可以登錄。

 

能夠查看簡潔版的：MySQL 鏈接方式

更多細節能夠查看 ：http://blog.itpub.net/15480802/viewspace-1755100/