Elastic Beanstalk Nginx代理抛出502 Bad Gateway

Question

I have a simple MEAN application, which I compose using a Mongo image and a Node + Express image. I use Elastic Beanstalk to create a Docker Application. I am able to create an environment successfully. EB dashboard tells me that both the application and the environment were successfully created.

However the URL for my EB instance gives me a 502 Bad Gateway. I researched this error in relation to Beanstalk and variously tried:

• Adding a NodeCommand: "npm start" property to .ebextensions/node-command.config which gave me a Duplicate or Invalid property error.

• Mimicking the way the project is started as detailed in this repo: https://github.com/shippableSamples/sample_node_eb_docker/tree/tutorial I am following this tutorial; http://blog.shippable.com/how-to-deploy-to-elastic-beanstalk-part-2 , which uses the aforementioned project as an example. Basically, I moved the app.listen code under bin/www

None of these approaches worked.

My Dockerfile

FROM node:7
RUN mkdir -p /usr/src/rishighan

WORKDIR /usr/src/rishighan

COPY package.json /usr/src/rishighan
COPY bower.json /usr/src/rishighan

#Install dependencies
RUN npm i -g bower  && \
npm i  && \
bower i --config.interactive=false --allow-root

RUN npm rebuild node-sass

COPY . /usr/src/rishighan
EXPOSE 80

# This starts the app
CMD npm start

docker-compose.yml

# find a way to seed the mongo db
version: '3.2'
services:
  mongodb:
    build:
      context: ./
      dockerfile: mongo-seed/Dockerfile
  web:
    build: .
    command: node server.js
    volumes:
      - .:/usr/src/rishighan
    ports:
      - "3000:3000"
    links:
     - mongodb
    environment:
      PORT: 3000 # this is optional, allows express to use process.env.PORT instead of a raw 3000

Dockerrun.aws.json

 {
  "AWSEBDockerrunVersion": "1",
  "Image": {
  "Name": "frishi/rishighanangular_web:nativeEBDeployment",
  "Update": "true"
 },
 "Ports": [
  {
    "ContainerPort": "80"
  }
 ],
  "Volumes": [
 ]
}

Relevant bits of my package.json

  "scripts": {
    "dev": "webpack-dev-server --content-base app/ --hot --inline",
    "start": "webpack -w --debug --devtool eval --output-pathinfo",
    "local-dev": "node server.js",
    "test": "testem ci"
  }

Relevant bits of my server.js

// Start Server on 3000
let port = process.env.PORT || 3000;
app.listen(port, function () {
    console.log("Server listening on port ", port);
});

I also found an answer on SO that suggested overriding the nginx.conf before Beanstalk sets it. I was able to download logs from EB and they are as follows:

nginx error.log

2017/07/24 12:10:47 [error] 3378#0: *8824 connect() failed (111: Connection refused) while connecting to upstream, client: 10.65.133.248, server: , request: "GET / HTTP/1.1", upstream: "http://172.17.0.2:80/", host: "54.243.122.6"
2017/07/24 13:27:16 [error] 3378#0: *9903 connect() failed (111: Connection refused) while connecting to upstream, client: 10.164.151.69, server: , request: "GET /xmlrpc.php HTTP/1.1", upstream: "http://172.17.0.2:80/xmlrpc.php", host: "54.197.241.240"
2017/07/24 13:29:18 [error] 3378#0: *9946 connect() failed (111: Connection refused) while connecting to upstream, client: 10.164.151.69, server: , request: "GET / HTTP/1.1", upstream: "http://172.17.0.2:80/", host: "54.197.241.240"
2017/07/24 14:17:28 [error] 3378#0: *10615 connect() failed (111: Connection refused) while connecting to upstream, client: 10.65.133.248, server: , request: "GET / HTTP/1.1", upstream: "http://172.17.0.2:80/", host: "rishighan-angular-dev.us-east-1.elasticbeanstalk.com"
2017/07/24 14:17:28 [error] 3378#0: *10615 connect() failed (111: Connection refused) while connecting to upstream, client: 10.65.133.248, server: , request: "GET /favicon.ico HTTP/1.1", upstream: "http://172.17.0.2:80/favicon.ico", host: "rishighan-angular-dev.us-east-1.elasticbeanstalk.com", referrer: "http://rishighan-angular-dev.us-east-1.elasticbeanstalk.com/"

I would appreciate any pointers as to where to start looking for potential causes of the error.

Answer 1

Had a similar issue myself, and the problem was that nginx connects to node.js on port 8081 by default. I can see in your code that you're trying to listen on port 3000 by default.