docker实现mysql主从复制

docker实现mysql主从复制

1. 下载mysql docker image

docker pull mysql

参考：
镜像地址

2. 创建一个mysql容器

docker run -t --name mysql -p 3306:3306 -e MYSQL_ROOT_PASSWORD='123456' -d  mysql

3. 实现主从复制

创建主mysql服务器

docker run -t --name mysql-master -p 3307:3306 -e MYSQL_ROOT_PASSWORD='123456' -d  mysql

创建从mysql服务器

docker run -t --name mysql-slave -p 3308:3306 -e MYSQL_ROOT_PASSWORD='123456' -d  mysql

4. mysql实现主从复制原理

通过binary logging来实现复制

4.1 在哪配置？

/etc/mysql/conf.d/

4.2 配置什么？

在

/etc/mysql/conf.d/

目录下添加*.cnf文件（名字随便取）

主服务器配置（master.cnf）

[mysqld]
log-bin=mysql-bin
server-id=1

从服务器(slave.cnf)

[mysqld]
#log-bin=mysql-bin #没必要启用 binary logging除非 从服务器 要作为其他服务器的 主服务器
server-id=2

4.3 docker如何将上面的配置加入到之前创建的

mysql-master

及

mysql-slave

直接将文件复制到容器的相应木目录下,然后重启容器

docker cp master.cnf mysql-master:/etc/mysql/my.cnf
docker cp slave.cnf mysql-master:/etc/mysql/my.cnf

4.4 主服务器创建一个具有复制权相的用户

docker进入mysql命令行

docker exec -it mysql-master mysql -uroot -p123456

创建复制权限用户并赋予相关权限

CREATE USER 'repl'@'%' IDENTIFIED BY '123456';       -- '%'意味着所有的终端都可以用这个用户登录
GRANT SELECT,REPLICATION SLAVE ON *.* TO 'repl'@'%'; -- SELECT权限是为了让repl可以读取到数据，生产环境建议创建另一个用户

从服务器连接到主服务器

docker exec -it mysql-slave mysql -uroot -p123456

CHANGE MASTER TO MASTER_HOST='192.168.99.100',MASTER_PORT=3308, MASTER_USER='repl', MASTER_PASSWORD='123456';
START SLAVE;
SHOW SLAVE STATUS\G       -- \G用来代替";"，能把查询结果按键值的方式显示

由于刚开始没有配置主服务器的端口导致如下错误运行结果

mysql> mysql> show slave status \G
*************************** 1. row ***************************
Slave_IO_State: Connecting to master
Master_Host: 192.168.99.100
Master_User: repl
Master_Port: 3306
Connect_Retry: 60
Master_Log_File:
Read_Master_Log_Pos: 4
Relay_Log_File: d0f565d3c84f-relay-bin.000001
Relay_Log_Pos: 4
Relay_Master_Log_File:
Slave_IO_Running: Connecting
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: 0
Relay_Log_Space: 154
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: 2003
Last_IO_Error: error connecting to master 'repl@192.168.99.100:3306' - retry-time: 60  retries: 2
Last_SQL_Errno: 0
Last_SQL_Error:
Replicate_Ignore_Server_Ids:
Master_Server_Id: 0
Master_UUID:
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: 170622 08:50:54
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)

正确运行结果

mysql> change master to
-> master_host='192.168.99.100'
-> master_port=3308
-> master_user='repl';
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_port=3308
master_user='repl'' at line 3
mysql> change master to master_host='192.168.99.100',master_port=3308,master_user='repl',master_passwrod='123456';
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_passwrod='123456'' at line 1
mysql> change master to master_host='192.168.99.100',master_port=3308,master_user='repl',master_password='123456';
Query OK, 0 rows affected, 2 warnings (0.03 sec)

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

mysql> show slave status \G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.99.100
Master_User: repl
Master_Port: 3308
Connect_Retry: 60
Master_Log_File: mysql-bin.000001
Read_Master_Log_Pos: 313
Relay_Log_File: d0f565d3c84f-relay-bin.000002
Relay_Log_Pos: 526
Relay_Master_Log_File: mysql-bin.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: 313
Relay_Log_Space: 740
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: 2b3c5dee-5722-11e7-8ddb-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)

5. 测试

在

mysql-master

执行如下操作

CREATE DATABASE test;

查看

mysql-slave

中也会创建相关的数据库，至此，主从备份搞定。

参考官网

Chapter 16 Replication

基于docker的MySQL主从复制（replication）