错误 2002 (HY000)：无法连接到 'db' 上的 MySQL 服务器 (115)

Question

我正在尝试将现有项目移动到 Docker。我在 M.Academy and followed the setup instructions from Docker on Existing Project

上学习了本教程

在执行尝试与 MySQL 连接时出现此错误 错误 2002 (HY000)：无法连接到 'db' 上的 MySQL 服务器（ 115)

我也试过执行：telnet db 3306

回复：正在尝试 172.17.0.1... telnet：无法连接到远程主机：连接超时

我尝试了所有方法，但无法找出问题所在。我是 Docker 的新手。我正在使用 Ubuntu 18.04 LTE。没有更改 db.env 并且在导入数据库之前的任何其他步骤都没有错误。

我进一步检查发现容器无法与MySQL建立连接。

P.S。我可以通过使用（外部 MySQL 端口）mysql -h 127.0.01 -u root -p -P 3306

成功连接 Docker 容器外的相同 MySQL 服务

重现步骤

在 Ubuntu 18.04
下载 Docker 撰写模板：curl -s https://raw.githubusercontent.com/markshust/docker-magento/master/lib/template | bash
替换为现有 Magento 实例的现有源代码：cp -R ~/Sites/existing src
执行：docker-compose -f docker-compose.yml up -d
将文件复制到容器：bin/copytocontainer --all
导入现有数据库：bin/mysql < /var/www/magento243.sql

预期结果 数据库应该已经成功导入

实际结果 错误 2002 (HY000)：无法连接到 'db' (115)

上的 MySQL 服务器

P.S。此处已提出问题：https://github.com/markshust/docker-magento/issues/589

docker-compose.yml

version: "3"

services:
  app:
    image: markoshust/magento-nginx:1.18-5
    ports:
      - "80:8000"
      - "443:8443"
    depends_on:
      - "db"
    volumes: &appvolumes
      - ~/.composer:/var/www/.composer:cached
      - ~/.ssh/id_rsa:/var/www/.ssh/id_rsa:cached
      - ~/.ssh/known_hosts:/var/www/.ssh/known_hosts:cached
      - appdata:/var/www/html
      - sockdata:/sock
      - ssldata:/etc/nginx/certs
    extra_hosts: &appextrahosts
      ## M1 Mac support to fix Docker delay, see #566
      - "app:172.17.0.1"
      - "phpfpm:172.17.0.1"
      - "db:172.17.0.1"
      - "redis:172.17.0.1"
      - "elasticsearch:172.17.0.1"
      - "rabbitmq:172.17.0.1"
      ## Selenium support, replace "magento.test" with URL of your site
      - "magento.test:172.17.0.1"

  phpfpm:
    image: markoshust/magento-php:7.4-fpm-11
    volumes: *appvolumes
    extra_hosts: *appextrahosts
    env_file: env/phpfpm.env

  db:
    image: mariadb:10.4
    command: --max_allowed_packet=256M
    ports:
      - "3306:3306"
    env_file: env/db.env
    volumes:
      - dbdata:/var/lib/mysql
    extra_hosts: *appextrahosts

  redis:
    image: redis:5.0-alpine
    ports:
      - "6379:6379"
    extra_hosts: *appextrahosts

  elasticsearch:
    image: markoshust/magento-elasticsearch:7.9.3-1
    ports:
      - "9200:9200"
      - "9300:9300"
    environment:
      - "discovery.type=single-node"
      ## Set custom heap size to avoid memory errors
      - "ES_JAVA_OPTS=-Xms1g -Xmx1g"
      ## Avoid test failures due to small disks
      ## More info at https://github.com/markshust/docker-magento/issues/488
      - "cluster.routing.allocation.disk.threshold_enabled=false"
      - "index.blocks.read_only_allow_delete"
    extra_hosts: *appextrahosts

  rabbitmq:
    image: rabbitmq:3.8.22-management-alpine
    ports:
      - "15672:15672"
      - "5672:5672"
    volumes:
      - rabbitmqdata:/var/lib/rabbitmq
    environment:
      - RABBITMQ_VM_MEMORY_HIGH_WATERMARK=1GB
    extra_hosts: *appextrahosts

  mailcatcher:
    image: sj26/mailcatcher
    ports:
      - "1080:1080"
    extra_hosts: *appextrahosts

  ## Selenium support, uncomment to enable
  #selenium:
  #  image: selenium/standalone-chrome-debug:3.8.1
  #  ports:
  #    - "5900:5900"
  #  extra_hosts: *appextrahosts

volumes:
  appdata:
  dbdata:
  rabbitmqdata:
  sockdata:
  ssldata:

Answer 1

此问题最终由

解决

正在从 YML 文件中删除 extra_hosts 条目
在YML

网络

决赛docker-compose.yml

version: "3"

services:
  app:
    image: markoshust/magento-nginx:1.18-5
    ports:
      - "81:8000"
      - "444:8443"
    depends_on:
      - "db"
    volumes: &appvolumes
      - ~/.composer:/var/www/.composer:cached
      - ~/.ssh/id_rsa:/var/www/.ssh/id_rsa:cached
      - ~/.ssh/known_hosts:/var/www/.ssh/known_hosts:cached
      - appdata:/var/www/html
      - sockdata:/sock
      - ssldata:/etc/nginx/certs
    networks:
      - customNetwork

  phpfpm:
    image: markoshust/magento-php:7.4-fpm-11
    volumes: *appvolumes
    env_file: env/phpfpm.env
    networks:
      - customNetwork

  db:
    image: mariadb:10.4
    command: --max_allowed_packet=256M
    ports:
      - "3307:3306"
    env_file: env/db.env
    volumes:
      - dbdata:/var/lib/mysql
    networks:
      - customNetwork

  redis:
    image: redis:5.0-alpine
    ports:
      - "6379:6379"
    networks:
      - customNetwork

  elasticsearch:
    image: markoshust/magento-elasticsearch:7.9.3-1
    ports:
      - "9201:9200"
      - "9301:9300"
    environment:
      - "discovery.type=single-node"
      ## Set custom heap size to avoid memory errors
      - "ES_JAVA_OPTS=-Xms1g -Xmx1g"
      ## Avoid test failures due to small disks
      ## More info at https://github.com/markshust/docker-magento/issues/488
      - "cluster.routing.allocation.disk.threshold_enabled=false"
      - "index.blocks.read_only_allow_delete"
    networks:
      - customNetwork

  rabbitmq:
    image: rabbitmq:3.8.22-management-alpine
    ports:
      - "15672:15672"
      - "5672:5672"
    volumes:
      - rabbitmqdata:/var/lib/rabbitmq
    environment:
      - RABBITMQ_VM_MEMORY_HIGH_WATERMARK=1GB
    networks:
      - customNetwork

  mailcatcher:
    image: sj26/mailcatcher
    ports:
      - "1080:1080"
    networks:
      - customNetwork

volumes:
  appdata:
  dbdata:
  rabbitmqdata:
  sockdata:
  ssldata:

networks:
  customNetwork:

错误 2002 (HY000)：无法连接到 'db' 上的 MySQL 服务器 (115)

ERROR 2002 (HY000): Can't connect to MySQL server on 'db' (115)

mysql

linux

magento

docker