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How to set up NGINX Docker Reverse Proxy?

Sukhbir Sekhon on April 25, 2020

Introduction Imagine a time when you set up the local server and created a front-end application based on it. To access the API of an ap...

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Alara Oluwatoyin Joel • Jul 21 '20

Great write Sukhbir, trying to follow it but my situation is quite different.
I have a server that runs Nginx, and I am deploying a CMS (Xibo) on it.
Cms runs by default on port 80, but cannot run because Nginx is listening there.
So to run it I kill the Nginx process.
Note that the cms is running inside of a docker-compose container.

So I am supposed to change its port, then use a reverse proxy to bring it back on port 80, when this works on HTTP, then I can do the securing
Phew!!
You did help understand things better, so i will keep hacking away.

davbaster • Dec 2 '20 • Edited

Hi,
I have completed this tutorial, and it helped me a lot, however I needed to do a couple of changes in order to work on my side.

First, I changed the name of the networks, since on my side they were called webservice1_default instead of site1_default. I found the name of the network by executing this docker command: "docker network ls"

dev-to-uploads.s3.amazonaws.com/i/...

Second, I had to found out which were my containers' ip, since the ones listed here are different than mine. I found the ips by inspecting the networks I found before. I used "docker network inspect NameOfYourNetwork" command.

dev-to-uploads.s3.amazonaws.com/i/...

Third, I had to modify my hosts file with the correct ips I found in the previous step.

dev-to-uploads.s3.amazonaws.com/i/...

Finally, I needed to do some modifications in docker-compose.yml file for the proxy, since the identitation was no correct. In the below image you can see the correct identation.

dev-to-uploads.s3.amazonaws.com/i/...

Thanks to the author for taking the time to do this tutorial.

xkozs01 • Aug 4 '20

Can you please fix the indentation in the yml files? I cannot build the docker-compose.yml for proxy server (the last yml in the article)

Sukhbir Sekhon • Aug 4 '20

Try copying the code using ALT instead of CTRL.

xkozs01 • Aug 5 '20

Thanks for response, but how can I use ALT istead of CTRL? It doesn't work on my Windows notebook. I am pasting it to VS Code. When I format it like this

version: '2'
services:
  proxy:
    build: ./
    networks:
      - site1
      - site2
    ports:
      - "80:80"
      - "443:443"

  networks:
    site1:
      external:
        name: site1_default
    site2:
      external:
        name: site2_default

It gives me an error

ERROR: The Compose file '.\docker-compose.yml' is invalid because:
Unsupported config option for services.networks: 'site2'

What is wrong?

xkozs01 • Aug 5 '20

OK, I got it, but it took me some time to figure it out

Webservice 1

version: "2"
services:
  app:
    image: nginx:1.9
    volumes:
      - .:/usr/share/nginx/html/
    expose:
      - "80"

Webservice 2

version: "2"
services:
  app:
    image: nginx:1.9
    volumes:
      - .:/usr/share/nginx/html/
    expose:
      - "80"

proxy

version: "2"
services:
  proxy:
    build: ./
    networks:
      - site1
      - site2
    ports:
      - "80:80"
      - "443:443"

networks:
  site1:
    external:
      name: site1_default
  site2:
    external:
      name: site2_default

RICARDO RAUL JACINTO MONTES • Mar 19 '21

First at all, thanks !!! great tutorial, with some mistakes it's true, but it shows cooperation of all involved. I followed not only this blog, but the instructions from davbaster and it worked well.

Thanks again

Alver Grisales • Aug 27 '20

hi, the implementation i have error

host not found in upstream "site1_app_1" in /etc/nginx/conf.d/default.conf:14

Nicolas G • Oct 25 '20 • Edited

Hello
This tutorial does not work, but I success with another
1- A part is missing ; The site1_default and site2_default networks should be created before,

2- The container names site1_app_1 and site2_app_1 are not defined, because autogenerated by docker : in my Docker version it generates webservice1_app_1 and webservice1_app_2. The best practice is to give a name to containers in the docker-compose.yml file, using the "container_name" keyword .
3- Cannot resolve the container names inside the Nginx container : so the proxy_pass directive dos not work, I think I must configure something in my Docker configuration, but it is not explained in this tutorial
4- Let's encrypt does not work generate the certificates because the server does not exist in the DNS ( pointer A missing)
5- site1.test and site2.test are bad declared in the /etc/hosts file . Normally you should declare in one line, like that : "172.31.30.78 site1.test site2.test"
Best regards