【Mysql】主从环境搭建步骤详解

一. 架构图
软件版本：Linux、Mysql Server version: 5.6.15




二.操作过程

2.1 主从机各自配置my.cnf文件，此文件默认位置在/etc/my.cnf,无的可以直接从/usr/share/mysql/my-default.cnf复制过来并改名就可以了。文件后加入以下内容：

log-bin=mysql-bin   //[必须]启用二进制日志
server-id=222      //[必须]服务器唯一ID，默认是1，一般取IP最后一段,主从机ID不能一样
replicate-do-db = test //[可选] 指定复制的数据库
replicate-ignore-db = mysql,information_schema //[可选]指定不复制的数据库
slave-skip-errors    //[可选]在复制过程中，由于各种原因导致binlog中的sql出错，默认情况下，从库会停止复制，要用户介入。

2.2 重启mysql

***************************************主机操作******************************************

2.3 在主机上创建master用户，从机创建slave用户，注意，master用户需要有赋予slave复制的权利

2.4 登录master用户

GRANT REPLICATION SLAVE ON *.* to 'slave'@'%' identified by 'jan';

flush privileges;

2.5 停止对数据库的DDL和DML操作或lock起所有的数据库表，记录当前master的状态

mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000005 |      120 |              |                  |                   |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)

***************************************从机操作******************************************
2.6 执行以下语句指定master的IP，日志，日志记录位置信息，并启动slave

mysql> stop slave;
Query OK, 0 rows affected (0.03 sec)

mysql> change master to
->       master_host='192.168.232.128',
->       master_user='master',
->       master_password='jan',
->       master_log_file='mysql-bin.000005',
->       master_log_pos=120;
Query OK, 0 rows affected, 2 warnings (0.01 sec)

mysql> start slave;
Query OK, 0 rows affected (0.00 sec)

2.7 查看slave状态

mysql> show slave status\G;
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.232.128
Master_User: master
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000005
Read_Master_Log_Pos: 120
Relay_Log_File: localhost-relay-bin.000002
Relay_Log_Pos: 283
Relay_Master_Log_File: mysql-bin.000005
Slave_IO_Running: Yes   //此状态必须为YES
Slave_SQL_Running: Yes   //此状态必须为YES
Replicate_Do_DB:
Replicate_Ignore_DB:
Replicate_Do_Table:
Replicate_Ignore_Table:
Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
Last_Errno: 0
Last_Error:
Skip_Counter: 0
Exec_Master_Log_Pos: 120
Relay_Log_Space: 460
Until_Condition: None
Until_Log_File:
Until_Log_Pos: 0
Master_SSL_Allowed: No
Master_SSL_CA_File:
Master_SSL_CA_Path:
Master_SSL_Cert:
Master_SSL_Cipher:
Master_SSL_Key:
Seconds_Behind_Master: 0
Master_SSL_Verify_Server_Cert: No
Last_IO_Errno: 0
Last_IO_Error:
Last_SQL_Errno: 0
Last_SQL_Error:
Replicate_Ignore_Server_Ids:
Master_Server_Id: 1
Master_UUID: 2b913f38-8dd4-11e5-aa5d-000c29271917
Master_Info_File: /var/lib/mysql/master.info
SQL_Delay: 0
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State: Slave has read all relay log; waiting for the slave I/O thread to update it
Master_Retry_Count: 86400
Master_Bind:
Last_IO_Error_Timestamp:
Last_SQL_Error_Timestamp:
Master_SSL_Crl:
Master_SSL_Crlpath:
Retrieved_Gtid_Set:
Executed_Gtid_Set:
Auto_Position: 0
1 row in set (0.00 sec)

从上述信息可知已经成功搭建主从库并联通了，但在搭建过程中遇到一些错误：
Slave_IO_Running:Yes

Slave_SQL_Running:No
解决方法：master用户没有配置权限给slave用户，授权即可
若还是无法解决问题，可查找binlog日志

show binlog event in 'master-bin.000005'\G ;

三.测试

3.1 创建数据库
master：

mysql> create database testdb;
Query OK, 1 row affected (0.00 sec)

slave：

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| testdb             |
+--------------------+
4 rows in set (0.00 sec)

3.2 更新数据

master:

mysql> create table a(id int(10),name varchar(20));
Query OK, 0 rows affected (0.02 sec)

mysql> insert into a values(1,'jan'),(2,'lulu');
Query OK, 2 rows affected (0.00 sec)
Records: 2  Duplicates: 0  Warnings: 0

slave:

mysql> select * from a;
+------+------+
| id   | name |
+------+------+
|    1 | jan  |
|    2 | lulu |
+------+------+
2 rows in set (0.01 sec)

本文出自 “之乎者也” 博客，请务必保留此出处http://yongjian2013.blog.51cto.com/2507427/1722014