mysql数据库互为主从配置

mysql主从配置小记：

共有四台机器：A(10.1.10.28),B(10.1.10.29),C(10.1.10.30),D(10.1.10.31)。
配置后结果：A-C互为主从，B为A的slave，D为C的slave。


0)准备工作

在四台机器上面安装好mysql后，创建用于同步的账号。

添加账户：

INSERT INTO user (Host,User, Password,Select_priv,Insert_priv,Update_priv,Delete_priv, Create_priv,Drop_priv) VALUES('%','test',password('test'),'Y','Y','Y','Y','Y','Y');

 
刷新数据库：

FLUSH PRIVILEGES;

1)配置A-C互为主从

修改A配置文件为：

server-id   = 1
replicate-do-db=test
replicate-do-db=test_admin
log-bin=mysql-bin
log-slave-updates
replicate-wild-do-table=test.%
replicate-wild-do-table=test_admin.%
binlog-ignore-db=mysql
slave-skip-errors=all

修改C配置文件为：

server-id   = 3
binlog-do-db=test
binlog-do-db=test_admin
log-bin=mysql-bin
log-slave-updates
replicate-wild-do-table=test.%
replicate-wild-do-table=test_admin.%
binlog-ignore-db=mysql
slave-skip-errors=all

重启mysql是配置生效

将A设置为主：
停止同步：

slave stop;

清空服务器master日志：

reset master;

授权同步账号：

GRANT REPLICATION SLAVE ON *.* TO 'test'@'%' IDENTIFIED BY 'test'；

刷新授权:

flush privileges;

 
锁定数据库:

flush tables with read lock;

 
将C设置为从：
停止同步：

slave stop;

 
配置同步信息：

CHANGE MASTER TO MASTER_HOST='10.1.10.28', MASTER_USER='test', MASTER_PASSWORD='test', MASTER_LOG_FILE='mysql-bin.000001', MASTER_LOG_POS=107;

 
将C设置为主：
停止同步：

slave stop;

清空服务器master日志：

reset master;

 
授权同步账号：

GRANT REPLICATION SLAVE ON *.* TO 'test'@'%' IDENTIFIED BY 'test'；

 
刷新授权:

flush privileges;

锁定数据库:

flush tables with read lock;

 
将A设置为从：
停止同步：

slave stop;

 
配置同步信息：

CHANGE MASTER TO MASTER_HOST='10.1.10.30', MASTER_USER='test', MASTER_PASSWORD='test', MASTER_LOG_FILE='mysql-bin.000001', MASTER_LOG_POS=107;

 
2)将B设置为A的从

server-id   = 2
replicate-do-db=test
replicate-do-db=test_admin
log-bin=mysql-bin
log-slave-updates
replicate-wild-do-table=test.%
replicate-wild-do-table=test_admin.%
binlog-ignore-db=mysql
slave-skip-errors=all

 

重启mysql服务

停止同步：

slave stop;

 
配置同步信息：

CHANGE MASTER TO MASTER_HOST='10.1.10.28', MASTER_USER='test', MASTER_PASSWORD='test', MASTER_LOG_FILE='mysql-bin.000001', MASTER_LOG_POS=107;

 
启动同步:

slave start;

 
3)将D设置为C的从

server-id   = 4
replicate-do-db=test
replicate-do-db=test_admin
log-bin=mysql-bin
log-slave-updates
replicate-wild-do-table=test.%
replicate-wild-do-table=test_admin.%
binlog-ignore-db=mysql
slave-skip-errors=all

 
重启mysql服务

停止同步：

slave stop;

 
配置同步信息：

CHANGE MASTER TO MASTER_HOST='10.1.10.30', MASTER_USER='test', MASTER_PASSWORD='test', MASTER_LOG_FILE='mysql-bin.000001', MASTER_LOG_POS=107;

 
启动同步:

slave start;

 完成之后可以创建添加数据测试一下是否可以。

下面是常见错误处理：

1）
change master导致的：
              Last_IO_Error: error connecting to master 'repl1@IP:3306' - retry-time: 60  retries

2）    
在没有解锁的情况下停止slave进程：
     mysql> stop slave;
ERROR 1192 (HY000): Can't execute the given command because you have active locked tables or an active transaction

3）
change master语法错误，落下逗号
mysql> change master to
    -> master_host='IP'
    -> master_user='USER',
    -> master_password='PASSWD',
    -> master_log_file='mysql-bin.000002',
    -> master_log_pos=106;
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'master_user='USER',
master_password='PASSWD',
master_log_file='mysql-bin.000002' at line 3

 
4）
在没有停止slave进程的情况下change master
mysql> change master to master_host=‘IP', master_user='USER', master_password='PASSWD', master_log_file='mysql-bin.000001',master_log_pos=106;
ERROR 1198 (HY000): This operation cannot be performed with a running slave; run STOP SLAVE first


5）
A B的server-id相同：
Last_IO_Error: Fatal error: The slave I/O thread stops because master and slave have equal MySQL server ids;
these ids must be different for replication to work (or the --replicate-same-server-id option must be used on
slave but this does not always make sense; please check the manual before using it).
查看server-id
mysql> show variables like 'server_id';
手动修改server-id
mysql> set global server_id=2; #此处的数值和my.cnf里设置的一样就行
mysql> slave start;

6）change master之后，查看slave的状态，发现slave_IO_running 为NO