Control points

If, as an expert of docker, you want to adapt the standard to the context of your project, you have to check that:


Steps (~15 min)

Install the nginx-proxy companion (~5 min)

  • Connect to your server ssh user@your.domain

  • Clone the nginx-proxy-companion project on the server at the root of the server.

git clone
  • Create a .env file

cd docker-compose-letsencrypt-nginx-proxy-companion
cp ./.env.sample .env
  • Set the NGINX_FILES_PATH=/srv/nginx/data in the .env

    • vim ./.env

    • line 41 replace NGINX_FILES_PATH=/srv/nginx/data(or a different path if you prefer)


Try to launch the companion by running:


You should have the following error because the port 80 is already used by your app docker:

ERROR: for nginx-web  Cannot start service nginx-web: driver failed programming external connectivity on endpoint nginx-web (4c0105fe57d370c99c0a143c967d1b8737006a4138618e1defebc4bab4e42d11): Bind for failed: port is already allocated

Configure your project to use the companion (~5 min)

  • Remove the binding 80 port command, but expose it

version: '3'
  your-web-app: #It should contain port: "80:80"
    # ... 
-   ports:
-     - "80:80"
+   expose:
+     - 80
  • Configure the app to use the network created by the companion (webproxy is the default name)

version: '3'
    # ... 

+  default:
+     external:
+        name: webproxy
  • In your project set 3 environment variable: VIRTUAL_HOST, LETSENCRYPT_HOST, LETSENCRYPT_EMAIL. The email will be used by Letsencrypt to notify you if the certificate expire.There are 2 ways:

    • In the docker-compose file

    • In your prod.env file that is read by your Dockerfile.


Update the .env file of your web-app docker

  • In the ./env/prod.env add the following:

#... other env variable

OTHER solution

If you have no .env file you an also Update the docker-compose-prod file

version: '3'
  your-web-app: #It should contain port: "80:80"
    # ... 
+      -
+      -
+      -

Make the switch (~5 min)


You will have to shut down your docker (so the port 80 is available), so during this step your domain won't be accessible.

  • Cut your app docker:

cd your-project-directory
docker-compose -f docker-compose-prod.yml down
  • Start the companion (go to the companion directory):

cd ../docker-compose-letsencrypt-nginx-proxy-companion
  • Launch your project docker again:

cd -
docker-compose -f docker-compose-prod.yml up -d


  • Check the validity of your domain, go to https://your.domain

  • Go there and check your domain. Useful tip: go to the Handshake Simulation section and check the supported devices.

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