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在之前的博客我们看了Docker 安装Mysql 容器，如下：
Redhat 7.7 系统上 Docker 安装 MySQL
https://www.cndba.cn/dave/article/4102
本篇博客我们了解下基于Docker 的MySQL主从环境搭建。
1 安装MySQL 容器
我们这里使用2台物理主机，分别安装好MySQL容器。
主库：192.168.74.202
从库：192.168.74.203
具体过程参考之前的博客，这里不再描述。
Redhat 7.7 系统上 Docker 安装 MySQL
https://www.cndba.cn/dave/article/4102
主库：
[root@www.cndba.cn_master ~]# docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
4e327b82cd18 192.168.74.203:5000/tomcat "catalina.sh run" 2 hours ago Up 2 hours 0.0.0.0:8080->8080/tcp tomcat
34ad82852c64 mysql:latest "docker-entrypoint.s…" 13 hours ago Exited (0) 2 hours ago mysqlserver
[root@www.cndba.cn_master ~]#
从库：
[root@www.cndba.cn_slave tomcat]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
mysql latest 9b51d9275906 3 weeks ago 547MB
registry latest 708bc6af7e5e 2 months ago 25.8MB
[root@www.cndba.cn_slave tomcat]# docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
f42c919cd98b mysql:latest "docker-entrypoint.s…" 18 seconds ago Up 16 seconds 0.0.0.0:3306->3306/tcp, 33060/tcp mysqlserver
6ae59667de8a registry "/entrypoint.sh /etc…" 3 hours ago Up 2 hours 0.0.0.0:5000->5000/tcp registry
[root@www.cndba.cn_slave tomcat]#
2 配置主从复制
2.1 修改mysql参数
docker 默认没有安装vim命令，需要提前安装，具体参考如下博客：
Docker 更改debian 源 并安装 vim 工具
https://www.cndba.cn/dave/article/4105
分别连接主从库容器，修改my.conf 参数文件。
主库添加如下内容：
[mysqld]
server_id = 1
log-bin= mysql-bin
read-only=0
root@34ad82852c64:/# cat /etc/mysql/my.cnf|grep -v "^#"
[mysqld]
pid-file = /var/run/mysqld/mysqld.pid
socket = /var/run/mysqld/mysqld.sock
datadir = /var/lib/mysql
secure-file-priv= NULL
symbolic-links=0
server_id = 1
log-bin= mysql-bin
read-only=0
!includedir /etc/mysql/conf.d/
root@34ad82852c64:/#
从库添加如下内容：
[mysqld]
server_id = 2
log-bin= mysql-bin
read-only=1
root@f42c919cd98b:/etc/apt# cat /etc/mysql/my.cnf|grep -v "^#"
[mysqld]
pid-file = /var/run/mysqld/mysqld.pid
socket = /var/run/mysqld/mysqld.sock
datadir = /var/lib/mysql
secure-file-priv= NULL
symbolic-links=0
server_id = 2
log-bin= mysql-bin
read-only=1
!includedir /etc/mysql/conf.d/
root@f42c919cd98b:/etc/apt#
分别重启主从库容器：
[root@www.cndba.cn_master ~]# docker restart mysqlserver
mysqlserver
[root@www.cndba.cn_master ~]#
[root@www.cndba.cn_slave ~]# docker restart mysqlserver
mysqlserver
[root@www.cndba.cn_slave ~]#
当然，在初始化容器的时候也可以将mysql的参数映射到本地路径，如下：
docker run —name slavemysql -d -p 3308:3306 -e MYSQL_ROOT_PASSWORD=root -v ~/test/mysql_test/slave/data:/var/lib/mysql -v ~/test/mysql_test/slave/conf/my.cnf:/etc/mysql/my.cnf mysql:5.7
2.2 主库创建同步用户并授权
[root@www.cndba.cn_master conf]# docker exec -it mysqlserver bash
root@34ad82852c64:/# mysql -uroot -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 8
Server version: 8.0.19 MySQL Community Server - GPL
Copyright (c) 2000, 2020, Oracle and/or its affiliates. All rights reserved.
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>CREATE USER 'slave'@'%' IDENTIFIED BY '123456';
Query OK, 0 rows affected (0.01 sec)
mysql> grant all on *.* to 'slave'@'%';
Query OK, 0 rows affected (0.00 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000001 | 856 | | | |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)
记住File、Position的值，在从库中会用到。
2.3 从库配置同步信息并启动slave
[root@www.cndba.cn_slave tomcat]# docker exec -it mysqlserver bash
root@f42c919cd98b:/# mysql -uroot -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or /g.
Your MySQL connection id is 9
Server version: 8.0.19 MySQL Community Server - GPL
Copyright (c) 2000, 2020, Oracle and/or its affiliates. All rights reserved.
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.
//设置主库链接
mysql> change master to master_host='192.168.74.202',master_user='slave',master_password='123456',master_log_file='mysql-bin.000001',master_log_pos=856,master_port=3306;
Query OK, 0 rows affected, 2 warnings (0.01 sec)
//启动从库同步
mysql> start slave;
Query OK, 0 rows affected (0.00 sec)
//查看状态
mysql> show slave status/G;
*************************** 1. row ***************************
Slave_IO_State: Connecting to master
Master_Host: 192.168.74.202
Master_User: slave
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000001
Read_Master_Log_Pos: 856
Relay_Log_File: f42c919cd98b-relay-bin.000001
Relay_Log_Pos: 4
Relay_Master_Log_File: mysql-bin.000001
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: 856
Relay_Log_Space: 155
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: NULL
Master_SSL_Verify_Server_Cert: No
Last_IO_Errno: 2061
Last_IO_Error: error connecting to master 'slave@192.168.74.202:3306' - retry-time: 60 retries: 3 message: Authentication plugin 'caching_sha2_password' reported error: Authentication requires secure connection.
Last_SQL_Errno: 0
Last_SQL_Error:
Replicate_Ignore_Server_Ids:
Master_Server_Id: 0
Master_UUID:
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: 200329 06:18:50
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:
Master_public_key_path:
Get_master_public_key: 0
Network_Namespace:
1 row in set (0.00 sec)
ERROR:
No query specified
如果 show slave status/G命令结果中出现： Slave_IO_Running: Yes Slave_SQL_Running: Yes 以上两项都为Yes，那说明没问题了。 但我们这里Slave_IO_Running状态不对，查看docker 日志，如下：
[root@www.cndba.cn_slave ~]# docker logs --tail 5 mysqlserver
2020-03-29T06:31:50.714902Z 10 [ERROR] [MY-010584] [Repl] Slave I/O for channel '': error connecting to master 'slave@192.168.74.202:3306' - retry-time: 60 retries: 16 message: Authentication plugin 'caching_sha2_password' reported error: Authentication requires secure connection. Error_code: MY-002061
2020-03-29T06:32:50.717568Z 10 [ERROR] [MY-010584] [Repl] Slave I/O for channel '': error connecting to master 'slave@192.168.74.202:3306' - retry-time: 60 retries: 17 message: Authentication plugin 'caching_sha2_password' reported error: Authentication requires secure connection. Error_code: MY-002061
2020-03-29T06:33:50.729106Z 10 [ERROR] [MY-010584] [Repl] Slave I/O for channel '': error connecting to master 'slave@192.168.74.202:3306' - retry-time: 60 retries: 18 message: Authentication plugin 'caching_sha2_password' reported error: Authentication requires secure connection. Error_code: MY-002061
2020-03-29T06:34:50.730994Z 10 [ERROR] [MY-010584] [Repl] Slave I/O for channel '': error connecting to master 'slave@192.168.74.202:3306' - retry-time: 60 retries: 19 message: Authentication plugin 'caching_sha2_password' reported error: Authentication requires secure connection. Error_code: MY-002061
2020-03-29T06:35:50.739934Z 10 [ERROR] [MY-010584] [Repl] Slave I/O for channel '': error connecting to master 'slave@192.168.74.202:3306' - retry-time: 60 retries: 20 message: Authentication plugin 'caching_sha2_password' reported error: Authentication requires secure connection. Error_code: MY-002061
[root@www.cndba.cn_slave ~]#
因为我们这里测试使用的是MySQL 8.0，在mysql8 之前的版本中加密规则是mysql_native_password,而在mysql8之后,加密规则是caching_sha2_password, 解决问题方法有两种,一种是升级navicat驱动,一种是把mysql用户登录密码加密规则还原成mysql_native_password. 我们这里使用旧的加密规则，在主库修改：
mysql> alter user 'slave'@'%' identified by '123456' password expire never;
Query OK, 0 rows affected (0.01 sec)
mysql> alter user 'slave'@'%' identified with mysql_native_password by '123456';
Query OK, 0 rows affected (0.01 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)
再次查看从库slave正常：
mysql> show slave status/G;
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.74.202
Master_User: slave
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000001
Read_Master_Log_Pos: 2742
Relay_Log_File: f42c919cd98b-relay-bin.000002
Relay_Log_Pos: 2208
Relay_Master_Log_File: mysql-bin.000001
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
2.4 验证同步
主库：
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
+--------------------+
4 rows in set (0.01 sec)
mysql> create database cndba;
Query OK, 1 row affected (0.00 sec)
mysql> use cndba;
Database changed
mysql> create table dave(username varchar(50),age int);
Query OK, 0 rows affected (0.02 sec)
mysql> insert into dave values('Dave',18);
Query OK, 1 row affected (0.01 sec)
mysql> select * from dave;
+----------+------+
| username | age |
+----------+------+
| Dave | 18 |
+----------+------+
1 row in set (0.00 sec)
mysql>
从库查询：
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| cndba |
| information_schema |
| mysql |
| performance_schema |
| sys |
+--------------------+
5 rows in set (0.00 sec)
mysql> use cndba;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> select * from dave;
+----------+------+
| username | age |
+----------+------+
| Dave | 18 |
+----------+------+
1 row in set (0.00 sec)
mysql>
主从同步正常。
我们这里演示的是新数据的同步，如果源库里已经有数据，那么就需要先将主库备份并恢复到从库，在配置同步。 至此基于Docker 的MySQL 8.0 主从同步环境搭建结束。
版权声明：本文为博主原创文章，未经博主允许不得转载。
