Nuxt应用Docker部署至Plesk服务器后出现Nginx 111错误与502网关错误求助

大家好，我把自己开发的Nuxt应用打包成Docker镜像，打算部署到Plesk服务器上，但遇到了棘手的问题：在浏览器输入域名后显示502 Bad Gateway错误，查看Nginx容器的日志发现是111错误（连接被拒绝）。我已经检查了防火墙、Docker网络连通性、容器状态，看起来都正常，但问题依然存在，恳请大家帮忙排查！

我的Docker Compose配置 #

version: '3.4'

services:
  busol_nuxt:
    container_name: busol_nuxt
    image: busol_nuxt
    ports:
      - "4000:4000"
    environment:
      NODE_ENV: production
    build:
      context: .
      dockerfile: ./Dockerfile
    volumes:
      - ./nuxt/dist:/usr/src/app/dist
    networks:
      - busol_network

  busol_nginx:
    image: nginx:latest
    container_name: nginx_front_nuxt
    volumes:
      - ./nginx/conf.d/default.conf:/etc/nginx/conf.d/default.conf
      - web-root:/var/www/blowstack
    ports:
      - "8080:8080"
    networks:
      - busol_network
    depends_on:
      - busol_nuxt
    restart: unless-stopped

networks:
  busol_network:
    driver: bridge

volumes:
  web-root:

Nginx默认配置文件（default.conf） #

upstream docker {
    server busol_nuxt:4000;
}

map $sent_http_content_type $expires {
    "text/html"                 epoch;
    "text/html; charset=utf-8"  epoch;
    default                     off;
}

server {
    listen          8080;             # the port nginx is listening on
    server_name     app.ariap.io;    # setup your domain here
    gzip            on;
    gzip_types      text/plain application/xml text/css application/javascript;
    gzip_min_length 1000;
    keepalive_timeout 650s;

    location / {
        expires $expires;
        proxy_ssl_verify off;  # désactive la vérification SSL
        proxy_redirect                      off;
        proxy_set_header Host               $host;
        proxy_set_header X-Real-IP          $remote_addr;
        proxy_set_header X-Forwarded-For    $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto  $scheme;
        proxy_connect_timeout       1m;
        proxy_pass                          http://docker;
        proxy_read_timeout 600s;
        fastcgi_buffers 8 500k;
        fastcgi_buffer_size 500k;
        fastcgi_connect_timeout 500s;
        fastcgi_send_timeout 500s;
        fastcgi_read_timeout 500s;
    }
}

Dockerfile配置 #

FROM node:lts-alpine

ENV NODE_ENV=production

WORKDIR /usr/src/app

COPY ["package.json", "package-lock.json*", "npm-shrinkwrap.json*", "./"]

RUN npm install --production --silent && mv node_modules ../

COPY . .

EXPOSE 4000

RUN chown -R node /usr/src/app

USER node

CMD ["npm", "start"]

当前问题现象与已排查项 #

• 浏览器访问域名时，页面显示502 Bad Gateway
• 查看Nginx容器日志，出现连接被拒绝的111错误
• 已经排查过的内容：
  • 服务器防火墙规则，确认4000、8080端口已开放
  • 两个容器都在同一个busol_network网络下，手动在Nginx容器内ping busol_nuxt可以连通
  • 两个容器均处于正常运行状态，无崩溃重启情况

备注：内容来源于stack exchange，提问作者Guei Josue