### 使用 Docker Compose 搭建 MySQL 一主两从集群 #### 准备工作 为了确保 MySQL 主从复制正常运行，需提前准备好必要的配置文件和目录结构。创建用于存储数据、日志以及配置文件的挂载点。 ```bash mkdir -p /home/mydata/mysql/{master,data_master,log_master,conf_master} mkdir -p /home/mydata/mysql/{slave1,data_slave1,log_slave1,conf_slave1} mkdir -p /home/mydata/mysql/{slave2,data_slave2,log_slave2,conf_slave2} ``` #### 编写 `docker-compose.yml` 文件 编写一个完整的 `docker-compose.yml` 来定义服务之间的关系和服务本身的属性： ```yaml version: '3' services: master: image: mysql:5.7 container_name: mysql-master environment: MYSQL_ROOT_PASSWORD: rootpassword ports: - "3306:3306" volumes: - /home/mydata/mysql/log_master:/var/log/mysql - /home/mydata/mysql/conf_master:/etc/mysql/conf.d command: mysqld --server-id=1 --log-bin=mysql-bin --binlog-format=mixed slave1: image: mysql:5.7 container_name: mysql-slave1 environment: MYSQL_ROOT_PASSWORD: rootpassword ports: - /home/mydata/mysql/data_slave1:/var/lib/mysql - /home/mydata/mysql/log_slave1:/var/log/mysql - /home/mydata/mysql/conf_slave1:/etc/mysql/conf.d depends_on: - master entrypoint: bash -c " sleep 10; until nc -z $$MYSQL_MASTER_HOST 3306; do echo waiting for master; sleep 2; done; exec mysqld --server-id=2 --relay-log=mysql-relay-bin --read-only --skip-slave-start & while ! mysqladmin ping -h$$MYSQL_MASTER_HOST --silent; do sleep 1; done; CHANGE MASTER TO MASTER_HOST='mysql-master',MASTER_USER='repl_user',MASTER_PASSWORD='replication_password',MASTER_LOG_FILE='mysql-bin.000001',MASTER_LOG_POS=154; START SLAVE; tail -f /dev/null" slave2: image: mysql:5.7 container_name: mysql-slave2 environment: MYSQL_ROOT_PASSWORD: rootpassword ports: - "3308:3306" volumes: - /home/mydata/mysql/data_slave2:/var/lib/mysql - /home/mydata/mysql/conf_slave2:/etc/mysql/conf.d depends_on: - master entrypoint: bash -c " sleep 10; until nc -z $$MYSQL_MASTER_HOST 3306; do echo waiting for master; sleep 2; done; exec mysqld --server-id=3 --relay-log=mysql-relay-bin --read-only --skip-slave-start & while ! mysqladmin ping -h$$MYSQL_MASTER_HOST --silent; do sleep 1; done; CHANGE MASTER TO MASTER_HOST='mysql-master',MASTER_USER='repl_user',MASTER_PASSWORD='replication_password',MASTER_LOG_FILE='mysql-bin.000001',MASTER_LOG_POS=154; START SLAVE; tail -f /dev/null" ``` 上述 YAML 文件描述了一个由三个节点组成的 MySQL 复制集：一个是主服务器(master)，另外两个是从服务器(slave)[^1]。 #### 启动服务 完成以上设置之后，在包含该 `docker-compose.yml` 文件所在的路径下执行命令来启动整个集群: ```bash docker-compose up -d ``` 这将会按照顺序依次启动各个容器，并自动建立好相应的主从同步关系。