无法连接外部dbgetaddrinfo上的Wordpress失败：名称或服务未知

Question

我想在Docker上运行我的WordPress站点，并且我想将WordPress数据库连接到另一个容器，该容器只有我所有站点的数据库。

为此，我使用以下docker-compose.yml创建了一个lamp容器：

version: "3"

services:
  web: 
    image: webdevops/php-apache:alpine-php7
    ports:
      - "4500:80"
    volumes: 
      - ./www:/app
      - ./uploads.ini:/opt/docker/etc/php/php.ini

  db:
    image: mysql
    command: --default-authentication-plugin=mysql_native_password
    restart: always
    environment:
      MYSQL_ROOT_PASSWORD: root
    ports:
      - "3306:3306"

  phpmyadmin:
    image: phpmyadmin/phpmyadmin
    environment:
      MYSQL_ROOT_PASSWORD: root
    ports:
      - "8088:80"

正如您所看到的，我已经使用WebDevOps映像安装了Apache作为服务，这将返回以下内容：

然后，我创建了一个具有WordPress实例的新容器：

version: '3'

    services:
      wordpress:
       depends_on:
         - db
       image: wordpress:latest
       volumes:
         - ./wp/wp-content:/var/www/html/wp-content
       ports:
         - "8000:80"
       restart: always
       environment:
         WORDPRESS_DB_HOST: lamp_db_1:3306
         WORDPRESS_DB_USER: root
         WORDPRESS_DB_PASSWORD: root
    
    volumes:
      dbdata:
      wp-content:

如您所见，我挂载了wp-content文件夹，因为我已经安装了带有插件和媒体的Wordpress...然后我尝试将此容器连接到lamp_db_1容器，但当我使用以下方式运行此容器时：

docker-compose up --build

我得到：

MySQL连接错误：（2002）php_network_getaddress:getaddrinfo失败：名称或服务未知

我做错了什么？

如何将wordpress容器连接到lamp容器？

Answer 1

您可以在lamp堆栈中指定自定义网络，并通过在Compose中使用network.external参数，使wordpress堆栈和其他Compose文件中定义的其他容器使用此网络。

在同一个网络中，您将能够使用lamp_db容器的容器名作为主机名加入它。

一个完整的例子：

version: '3.5'
services:
  db:
    # This will be the hostname for your DB container on the network
    container_name: lamp_db
    image: mysql
    ports:
    - 3306:3306
    environment:
      MYSQL_ROOT_PASSWORD: root
    # Have db container join our db network
    networks:
    - db_network

# Ensure our custom network is managed by this stack
networks:
  db_network:
    name: db_network

version: '3.5'

services:
  wordpress:
    image: wordpress:latest
    ports:
    - "8000:80"
    environment:
      # Name of the db container
      WORDPRESS_DB_HOST: lamp_db:3306
      WORDPRESS_DB_USER: root
      WORDPRESS_DB_PASSWORD: root
    # Have wordpress container join our db network
    networks:
    - db_network

# Declare db_network as external with it's name
# Network won't be created by this stack but must exists before running
# See https://docs.docker.com/compose/compose-file/#external-1
networks:
  db_network:
    external: true
    name: db_network

以及需要使用数据库的任何服务的通用示例：

version: '3.5'

services:
  some_container:
    image: some-image:latest
    # Have this container join our db network
    networks:
    - db_network
    # Note: make sure to reference db container by it's hostname lamp_db

networks:
  db_network:
    external: true
    name: db_network

备注：

• db_network通过lamp堆栈进行管理。当up进入lamp堆栈时，Docker Compose将确保创建此网络。使用此网络的其他堆栈应将其声明为external:truewith其名称
• 您需要版本：“3.5”或更高版本才能使用Network.NameConfig