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一、Docker中实现跨服务器主从备份

在 Docker 中配置 MySQL 主从备份主要通过 MySQL 主从复制实现

二、配置步骤

1.配置主库

# 进入mysql主库容器
docker exec -it mysql-master bash

# 连接mysql
mysql -127.0.0.1 ip -P 3306 -uroot -p 'password'

# 创建用于从库连接的用户
CREATE USER 'replica_user'@'%' IDENTIFIED WITH 'mysql_native_password' BY 'replica_password';
GRANT REPLICATION SLAVE ON *.* TO 'replica_user'@'%';
FLUSH PRIVILEGES;

# 检查二进制日志状态(记录File和Position)
SHOW MASTER STATUS;

2.配置从库

# 进入mysql主库容器
docker exec -it mysql-slave bash

# 连接mysql
mysql -127.0.0.1 ip -P 3306 -uroot -p 'password'

-- 配置从库连接到主库
CHANGE MASTER TO
  MASTER_HOST='mysql-master',
  MASTER_PORT=3306,
  MASTER_USER='replica_user',
  MASTER_PASSWORD='replica_password',
  MASTER_LOG_FILE='binlog.000003',
  MASTER_LOG_POS=932570,
  GET_MASTER_PUBLIC_KEY=1;

-- 启动从库复制
START SLAVE;

# 查看状态
SHOW SLAVE STATUS\G;

# 检查复制状态：确认以下两项为 Yes，表示复制成功
# Slave_IO_Running: Yes
# Slave_SQL_Running: Yes

3.遇到问题

Fatal error: The replica I/O thread stops because source and replica
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 replica but this does not always make sense; please check the
manual before using it).

• 主库与从库的id重复了，可以修改主库或者从库的id(mysql默认配置server-id=1)
  • 修改从数据库配置文件

[mysqld]
server-id=2
log-bin=mysql-bin
binlog-format=row
sql_mode=STRICT_TRANS_TABLES,NO_ENGINE_SUBSTITUTION
- 重启mysql容器

docker restart mysql-slave

- 使用配置遇到提醒

mysql: [Warning] World-writable config file ‘/etc/mysql/my.cnf’ is ignored.
这个警告 mysql: [Warning] World-writable config file ‘/etc/mysql/my.cnf’ is ignored. 通常表示 MySQL 配置文件 /etc/mysql/my.cnf 的权限设置不安全。MySQL 出于安全原因，会忽略权限设置为 “world-writable”（任何人都可写）的配置文件。
- 进入容器修改权限

docker exec -it mysql-server bash
chmod 644 /etc/mysql/my.cnf

3.其它使用到的命令

• 删除主从配置

# 停止从库的复制线程
STOP SLAVE;

# 清除主从复制配置
RESET SLAVE ALL;