MySQL复制(四)—多源(主)复制

MySQL复制(四)—多源(主)复制-LMLPHP

（一）多主复制概述

所谓多主复制，是将多个主库的数据复制到一个从库中。通常用于数据仓库整合数据，比如OLTP系统为了分散业务压力，对业务进行分库分表，当要对数据进行分析的时候，可以使用多主复制将数据整合到同一个数据库实例上，便于统一分析。MySQL从5.7版本开始支持多主复制。

MySQL复制(四)—多源(主)复制-LMLPHP

本文通过搭建多主复制环境来了解MySQL多主复制的特点。

（二）基础环境

	主库1	主库2	从库
服务器IP地址	192.168.10.11	192.168.10.12	192.168.10.13
MySQL版本	5.7.24	5.7.24	5.7.24
待同步的数据库	db1	db2	从库上创建空库db1和db2

（三）多主复制搭建

(3.1)创建用于复制的用户(主库执行)

在2个主数据库上创建用于复制的用户rep，用户需具有“replication slave”权限。每个数据库上复制账号可以不相同，这里为了测试方便，创建为相同的账号。

mysql> grant replication slave on *.* to 'rep'@'%' identified by '';

(3.2)参数修改（从库执行）

-- 重启数据库失效，建议配置在启动文件中

mysql> SET GLOBAL master_info_repository = 'TABLE';

mysql> SET GLOBAL relay_log_info_repository = 'TABLE';

(3.3)主库创建测试数据，备库创建空数据库

主库1：

mysql> create database db1;

mysql> use db1

mysql> create table test01

    -> (

    ->   id1   int  not null auto_increment,

    -> name  varchar(30),

    -> primary key(id1)

    -> );

mysql> insert into test01 values(1,'a');

主库2：

mysql> create database db2;

mysql> use db2

mysql> create table test02

    -> (

    ->   id2   int  not null auto_increment,

    -> name  varchar(30),

    -> primary key(id2)

    -> );

mysql> insert into test02 values(2,'b');

备库：

mysql> create database db1;

mysql> create database db2;

(3.4)将主库数据手动同步到备库（从库执行）

在备库上执行远程导出操作：

[root@slavedb ~]# mysqldump -uroot -p123456 -h192.168.10.  --master-data= --set-gtid-purged=OFF -P3306 db1 --single-transaction  > db1.sql

[root@slavedb ~]# mysqldump -uroot -p123456 -h192.168.10.  --master-data= --set-gtid-purged=OFF -P3306 db2 --single-transaction  > db2.sql

在备库上执行导入操作：

[root@slavedb ~]# mysql -h192.168.10. -P3306 -uroot -p123456 db1 < /root/db1.sql

[root@slavedb ~]# mysql -h192.168.10. -P3306 -uroot -p123456 db2 < /root/db2.sql

(3.5)开启从库同步db1（从库执行）

STEP1:确认主库1导出到的日志位置

cat db1.sql |grep "CHANGE MASTER"|less

-- CHANGE MASTER TO MASTER_LOG_FILE='master-bin.000029', MASTER_LOG_POS=;

STEP2：将主库1添加到复制环境

mysql> change master to

    -> master_host='192.168.10.11',

    -> master_port=3306,

    -> master_user='rep',

    -> master_password='',

    -> master_log_file='master-bin.000029',

    -> master_log_pos=1835

for channel 'ch1'

;

Query OK, 0 rows affected, 2 warnings (0.02 sec)

STEP3:开启主库1的复制

mysql> start slave

for channel 'ch1'

;

Query OK, 0 rows affected (0.00 sec)

(3.6)开启从库同步db2（从库执行）

STEP1:确认主库2导出到的日志位置

cat db2.sql |grep "CHANGE MASTER"|less

-- CHANGE MASTER TO MASTER_LOG_FILE='master-bin.000029', MASTER_LOG_POS=;

STEP2：将主库2添加到复制环境

change master to

master_host='192.168.10.12',

master_port=,

master_user='rep',

master_password='',

master_log_file='master-bin.000029',

master_log_pos= for channel 'ch2';

STEP3:开启主库2的复制

mysql> start slave for channel 'ch2';

(3.7)测试数据复制是否正常

主库1：

mysql> insert into test01 values(11,'aa');

主库2：

mysql> insert into test02 values(22,'bb');

备库：

mysql> select * from db1.test01;

+-----+------+

| id1 | name |

+-----+------+

|   1 | a    |

|  11 | aa   |

+-----+------+

2 rows in set (0.00 sec)

mysql> select * from db2.test02;

+-----+------+

| id2 | name |

+-----+------+

|   2 | b    |

|  22 | bb   |

+-----+------+

2 rows in set (0.00 sec

数据复制正常。

(3.8)确认复制状态

mysql> show slave status \G

*************************** 1. row ***************************

               Slave_IO_State: Waiting for master to send event

                  Master_Host: 192.168.10.11

                  Master_User: rep

                  Master_Port: 3306

                Connect_Retry: 60

              Master_Log_File: master-bin.000029

          Read_Master_Log_Pos: 1835

               Relay_Log_File: slavedb-relay-bin-ch1.000002

                Relay_Log_Pos: 321

        Relay_Master_Log_File: master-bin.000029

             Slave_IO_Running: Yes

            Slave_SQL_Running: 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: 1835

              Relay_Log_Space: 534

              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: caa64a22-481a-11ea-b0f1-000c29fb6200

             Master_Info_File: mysql.slave_master_info

                    SQL_Delay: 0

          SQL_Remaining_Delay: NULL

      Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates

           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: 8a885841-481c-11ea-bdc4-000c29840f0f:1-10,

caa64a22-481a-11ea-b0f1-000c29fb6200:1-466040

                Auto_Position: 0

         Replicate_Rewrite_DB:

                 Channel_Name: ch1

           Master_TLS_Version:

*************************** 2. row ***************************

               Slave_IO_State: Waiting for master to send event

                  Master_Host: 192.168.10.12

                  Master_User: rep

                  Master_Port: 3306

                Connect_Retry: 60

              Master_Log_File: master-bin.000029

          Read_Master_Log_Pos: 1419

               Relay_Log_File: slavedb-relay-bin-ch2.000002

                Relay_Log_Pos: 321

        Relay_Master_Log_File: master-bin.000029

             Slave_IO_Running: Yes

            Slave_SQL_Running: 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: 1419

              Relay_Log_Space: 534

              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: 2

                  Master_UUID: caa64a22-481a-11ea-b0f1-000c29fb6200

             Master_Info_File: mysql.slave_master_info

                    SQL_Delay: 0

          SQL_Remaining_Delay: NULL

      Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates

           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: 8a885841-481c-11ea-bdc4-000c29840f0f:1-10,

caa64a22-481a-11ea-b0f1-000c29fb6200:1-466040

                Auto_Position: 0

         Replicate_Rewrite_DB:

                 Channel_Name: ch2

           Master_TLS_Version:

2 rows in set (0.00 sec)

【完成】

附录：

MySQL复制(replication)文档集合:

1.复制概述
2.基于二进制日志文件位置(binlog)配置复制
3.基于全局事物标识符(GTID)配置复制
4.多源复制
5.级联复制
6.半同步复制
7.延迟复制
8.复制过滤规则
9.对复制进行故障排除
10.故障切换
11.复制管理