使用docker搭建dm主备集群

首先，需要安装Docker和Docker Compose。然后按照以下步骤操作：

1. 创建两个文件夹，分别为dm-master和dm-worker，用于存放主节点和从节点的配置文件。

2. 在dm-master文件夹中创建docker-compose.yml文件，并添加以下内容：

version: '3'
services:
  dm-master:
    image: pingcap/dm:latest
    container_name: dm-master
    volumes:
      - ./dm-master:/etc/dm-master
    ports:
      - "8261:8261"
      - "8291:8291"
    command: dm-master -config /etc/dm-master/dm-master.toml

3. 在dm-master文件夹中创建dm-master.toml配置文件，并添加以下内容：

[log.file]
filename = "/var/log/dm-master.log"

[log.level]
value = "info"

[server]
addr = ":8261"
advertise-addr = "master_ip:8261"
data-dir = "/data/dm-master"
name = "dm-master"

[dumpling-worker]
worker-addr = "worker_ip:8262"
password = "password"

[security]
ssl-ca = "/etc/dm-master/ca.pem"
ssl-cert = "/etc/dm-master/server-cert.pem"
ssl-key = "/etc/dm-master/server-key.pem"

注意将master_ip和worker_ip替换为实际的IP地址，并设置密码。

4. 在dm-worker文件夹中创建docker-compose.yml文件，并添加以下内容：

version: '3'
services:
  dm-worker:
    image: pingcap/dm:latest
    container_name: dm-worker
    volumes:
      - ./dm-worker:/etc/dm-worker
    ports:
      - "8262:8262"
    command: dm-worker -config /etc/dm-worker/dm-worker.toml

5. 在dm-worker文件夹中创建dm-worker.toml配置文件，并添加以下内容：

[log.file]
filename = "/var/log/dm-worker.log"

[log.level]
value = "info"

[server]
addr = ":8262"
advertise-addr = "worker_ip:8262"
data-dir = "/data/dm-worker"
name = "dm-worker"

[worker]
addr = ":8262"
password = "password"

[security]
ssl-ca = "/etc/dm-worker/ca.pem"
ssl-cert = "/etc/dm-worker/server-cert.pem"
ssl-key = "/etc/dm-worker/server-key.pem"

注意将worker_ip替换为实际的IP地址，并设置密码。

6. 在dm-master文件夹中创建ca.pem、server-cert.pem和server-key.pem证书文件，并将它们复制到dm-worker文件夹中。

7. 最后，在终端中进入dm-master文件夹，并执行以下命令启动主节点：

docker-compose up -d

8. 在终端中进入dm-worker文件夹，并执行以下命令启动从节点：

docker-compose up -d

现在，您已经成功地使用Docker搭建了DM主备集群。