使用docker进行MYSQL主从复制（一主两从）

目录

概述主从介绍

主从作用

主从作用有：

主从形式有：

 配置步骤

主要配置

1>创建三个进程

2>修改配置文件

3>主机配置

4>从机配置

5>将文件修改后，复制到容器里面

6>进入主机进行配置

6.1>创建用户

6.2>给用户授权

6.3>刷新权限

7>进入从机进行配置

对M1S1

对M2S2

 8>最后开启主从

9>测试

---

概述主从介绍

MySQL主从又叫Replication、AB复制。简单讲就是A与B两台机器做主从后，在A上写数据，另外一台B 也会跟着写数据，实现数据实时同步。有这样几个关键点：

1）MySQL主从是基于binlog，主上需开启binlog才能进行主从；

2）主从过程大概有3个步骤；

3）主将更改操作记录到binlog里；

4）从将主的binlog事件（SQL语句） 同步本机上并记录在relaylog里；

5）从根据relaylog里面的SQL语句按顺序执行。

主从作用

主从作用有：

实时灾备，用于故障切换；读写分离，提供查询服务；备份，避免影响业务。

主从形式有：

而我们今天的配置是一主两从

 配置步骤

1）确保从数据库与主数据库里的数据一致

2）在主数据库里创建一个同步账户授权给从数据库使用

3）配置主数据库（修改配置文件）

4）配置从数据库（修改配置文件）

5）需求

6）搭建两台MySQL服务器，一台作为主服务器，一台作为从服务器，主服务器进行写操作，从服务器 进行读操作

环境说明（使用docker通过不通端口启用多台mysql进程）

名称	IP	port
M1	192.168.38.132	3307
M1S1	192.168.38.132	3308
M1S2	192.168.38.132	3309

主要配置

1>创建三个进程

docker run --name M1 -p 3307:3306 -e MYSQL_ROOT_PASSWORD=123456 -d mysql:5.7 --
lower_case_table_names=1
docker run --name M1S1 -p 3308:3306 -e MYSQL_ROOT_PASSWORD=123456 -d mysql:5.7 -
-lower_case_table_names=1
docker run --name M1S2 -p 3308:3306 -e MYSQL_ROOT_PASSWORD=123456 -d mysql:5.7 -
-lower_case_table_names=1

2>修改配置文件

将容器里面的配置文件复制出来，主要修改服务器的配置；在root目录下创建一个mysqlms的目录存放 从Docker容器里面复制过来的配置文件。进入目录：cd /mysqlms

mkdir /mysqlms
cd /mysqlms
docker cp M1:/etc/mysql/conf.d/docker.cnf m1.cnf
docker cp M1S1:/etc/mysql/conf.d/docker.cnf m1s1.cnf
docker cp M1S2:/etc/mysql/conf.d/docker.cnf m1s2.cnf

3>主机配置

[root@localhost mysqlms]# vim m1.cnf

[mysqld]
skip-host-cache
skip-name-resolve
server-id=1
log-bin=master.bin

4>从机配置

[root@localhost mysqlms]# vim m1s1.cnf

[mysqld]
skip-host-cache
skip-name-resolve
server-id=3


[root@localhost mysqlms]# vim m1s2.cnf

[mysqld]
skip-host-cache
skip-name-resolve
server-id=2

然后记着重启三个进程

docker restart M1 M1S1 M1S2

5>将文件修改后，复制到容器里面

docker cp m1.cnf M1:/etc/mysql/conf.d/docker.cnf
docker cp m1s1.cnf M1S1:/etc/mysql/conf.d/docker.cnf
docker cp m1s2.cnf M1S2:/etc/mysql/conf.d/docker.cnf

6>进入主机进行配置

[root@localhost mysqlms]# docker exec -it M1 bash
root@40b67125e6ce:/#
root@40b67125e6ce:/# mysql -uroot -p123456

6.1>创建用户

mysql> create user 'rep'@'%' identified by '123456';
Query OK, 0 rows affected (0.01 sec)

6.2>给用户授权

mysql> grant replication slave on *.* to 'rep'@'%';
Query OK, 0 rows affected (0.01 sec)

6.3>刷新权限

mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)

此时我们使用M1里面的rep用户登录

root@40b67125e6ce:/# mysql -urep -p123456
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.7.36 MySQL Community Server (GPL)

Copyright (c) 2000, 2021, Oracle and/or its affiliates.

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.

mysql>

7>进入从机进行配置

对M1S1

[root@localhost mysqlms]# docker exec -it M1 bash
root@40b67125e6ce:/# mysql -uroot -p123456
mysql> change master to
    -> master_host="192.168.38.133",master_port=3307,
    -> master_user="rep",
    -> master_password="123456",
    -> master_log_file="master.000001",
    -> master_log_pos=154;
Query OK, 0 rows affected, 2 warnings (0.03 sec)

对M2S2

[root@localhost ~]# docker exec -it M1S2 bash
root@401c6f11cfc8:/# mysql -uroot -p123456
mysql> change master to
    -> master_host="192.168.38.133",master_port=3307,
    -> master_user="rep",
    -> master_password="123456",
    -> master_log_file="master.000001",
    -> master_log_pos=154;
Query OK, 0 rows affected, 2 warnings (0.01 sec)

其中，master_log_file：该文件具体叫什么名称，需要从主机里面去看看。进入M1 里面使用root 用户 登录M1，执行下面的SQL：show master status;

 8>最后开启主从

在M1S1和M2S2中都开启

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

最后查看主从状态

M1S1

mysql>  show slave status \G;
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 192.168.38.133
                  Master_User: rep
                  Master_Port: 3307
                Connect_Retry: 60
              Master_Log_File: master.000001
          Read_Master_Log_Pos: 154
               Relay_Log_File: ffe391517b79-relay-bin.000002
                Relay_Log_Pos: 317
        Relay_Master_Log_File: master.000001
             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: 154
              Relay_Log_Space: 531
              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: 9c13ed93-2971-11ee-8e34-0242ac110003
             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 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: 
                Auto_Position: 0
         Replicate_Rewrite_DB: 
                 Channel_Name: 
           Master_TLS_Version: 
1 row in set (0.00 sec)

M1S2

mysql>  show slave status \G;
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 192.168.38.133
                  Master_User: rep
                  Master_Port: 3307
                Connect_Retry: 60
              Master_Log_File: master.000001
          Read_Master_Log_Pos: 154
               Relay_Log_File: 401c6f11cfc8-relay-bin.000002
                Relay_Log_Pos: 317
        Relay_Master_Log_File: master.000001
             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: 154
              Relay_Log_Space: 531
              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: 9c13ed93-2971-11ee-8e34-0242ac110003
             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 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: 
                Auto_Position: 0
         Replicate_Rewrite_DB: 
                 Channel_Name: 
           Master_TLS_Version: 
1 row in set (0.00 sec)

9>测试

在M1 里面创建数据库，看M1S1 ,M1S2有没有复制过去

 

 

此时我们可以看到有了所以成功