Mysql配置主主同步

[TOC]

## 一.准备
1.两个数据库版本最好一致
2.两个数据库内数据保持一致，若不一致，可手动调整，比如A比B多一个库，那将这个库导入到B库，达到一致。

A数据库：182.92.172.80
B数据库：123.57.44.85

## 二.操作
### A数据库操作
1.开启binlog
`vim /etc/my.cnf`
```python
[mysqld]
log-bin=mysql-bin #开启二进制日志
server-id=1 #设置server-id，不能一样
```

2.重启mysql，创建用于同步的用户账号
`systemc restart mysql`

登陆数据库
`mysql -hlocalhost -uname -ppassword`

创建用户并授权：用户：test密码：123456，ip配置为B的IP
`CREATE USER 'test'@'123.57.44.85' IDENTIFIED BY '123456';`

分配权限
`GRANT REPLICATION SLAVE ON *.* TO 'test'@'123.57.44.85';`
`flush privileges;`

锁表，禁止写入，当前窗口不能退出，这时候开启另一个终端继续操作
`flush table with read lock;`

3.新窗口操作，查看master状态，记录二进制文件名(mysql-bin.000003)和位置(73)：
`SHOW MASTER STATUS;`
```python

+------------------+----------+--------------+------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+------------------+----------+--------------+------------------+
| mysql-bin.000003 | 73       |       |     |
+------------------+----------+--------------+------------------+
```

4.将当前数据导出，如果两数据库不一样，手动调整
`mysqldump -u root -p --all-databases > /root/alldb.sql`

5.解锁查看binlog日志位置，如果没变证明锁定成功。从库将从这个binlog日志开始恢复
`unlock table;`
```python
SHOW MASTER STATUS;

+------------------+----------+--------------+------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+------------------+----------+--------------+------------------+
| mysql-bin.000003 | 73       |       |     |
+------------------+----------+--------------+------------------+
```

### B数据库操作
1.导入数据
`mysql -uroot -p < alldb.sql`

2.修改配置文件
`vim /etc/my.cnf`
```python
[mysqld]
log-bin=mysql-bin #开启二进制日志
server-id=2 #设置server-id，必须唯一
```

3.重启mysql，配置同步
`systemctl restart mysql`

需要A服务器主机名，登陆凭据，二进制文件的名称和位置
`CHANGE MASTER TO MASTER_HOST='182.92.172.80', MASTER_USER='test', MASTER_PASSWORD='123456', MASTER_LOG_FILE='mysql-bin.000001', MASTER_LOG_POS=567;`
`start slave;`

4.查看slave状态：
`show slave status\G;`
```python
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 182.92.172.80
                  Master_User: rep1
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000013
          Read_Master_Log_Pos: 11662
               Relay_Log_File: mysqld-relay-bin.000022
                Relay_Log_Pos: 11765
        Relay_Master_Log_File: mysql-bin.000013
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes
              Replicate_Do_DB: 
          Replicate_Ignore_DB: 
        ...
```

Slave_IO_Running: Yes
Slave_SQL_Running: Yes
都是yes即可

5.配置作为A的主
创建用户并授权：用户：test密码：123456，ip配置为A的IP
`CREATE USER 'test'@'182.92.172.80' IDENTIFIED BY '123456';`

分配权限
`GRANT REPLICATION SLAVE ON *.* TO 'test'@'182.92.172.80';`
`flush privileges;`

这次不用锁表了，因为B在同步A的数据，当前保持一致了。

6.新窗口操作，查看master状态，记录二进制文件名(mysql-bin.000004)和位置(254)：
`SHOW MASTER STATUS;`
```python

+------------------+----------+--------------+------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+------------------+----------+--------------+------------------+
| mysql-bin.000004 | 254      |       |     |
+------------------+----------+--------------+------------------+
```

### A数据库操作
需要B服务器主机名，登陆凭据，二进制文件的名称和位置
`CHANGE MASTER TO MASTER_HOST='123.57.44.85', MASTER_USER='test', MASTER_PASSWORD='123456', MASTER_LOG_FILE='mysql-bin.000004', MASTER_LOG_POS=254;`
`start slave;`

4.查看slave状态：
`show slave status\G;`
```python
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 123.57.44.85
                  Master_User: rep1
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000013
          Read_Master_Log_Pos: 11662
               Relay_Log_File: mysqld-relay-bin.000022
                Relay_Log_Pos: 11765
        Relay_Master_Log_File: mysql-bin.000013
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes
              Replicate_Do_DB: 
          Replicate_Ignore_DB: 
        ...
```

Slave_IO_Running: Yes
Slave_SQL_Running: Yes
都是yes即可

Mysql配置 主主同步

Mysql配置主主同步