letsencrypt-nginx-proxy-companion is a lightweight companion container for the nginx-proxy. It allow the creation/renewal of Let's Encrypt certificates automatically. See Let's Encrypt section for configuration details.

Features:

• Automatic creation/renewal of Let's Encrypt certificates using original nginx-proxy container.
• Support creation of Multi-Domain (SAN) Certificates.
• Automatically creation of a Strong Diffie-Hellman Group (for having an A+ Rate on the Qualsys SSL Server Test).
• Work with all versions of docker.

NOTE: The first time this container is launch it generate a new Diffie-Hellman group file. This process can take several minutes to complete (be patient).

Usage

To use it with original nginx-proxy container you must declare 3 writable volumes from the nginx-proxy container:

• /etc/nginx/certs to create/renew Let's Encrypt certificates
• /etc/nginx/vhost.d to change the configuration of vhosts (need by Let's Encrypt)
• /usr/share/nginx/html to write challenge files.

Example of use:

• First start nginx with the 3 volumes declared:

$ docker run -d -p 80:80 -p 443:443 \
    --name nginx-proxy \
    -v /path/to/certs:/etc/nginx/certs:ro \
    -v /etc/nginx/vhost.d \
    -v /usr/share/nginx/html \
    -v /var/run/docker.sock:/tmp/docker.sock:ro \
    jwilder/nginx-proxy

• Second start this container:

$ docker run -d \
    -v /path/to/certs:/etc/nginx/certs:rw \
    --volumes-from nginx-proxy \
    -v /var/run/docker.sock:/var/run/docker.sock:ro \
    jrcs/letsencrypt-nginx-proxy-companion

Then start any containers you want to proxied with a env var VIRTUAL_HOST=subdomain.youdomain.com

$ docker run -e VIRTUAL_HOST=foo.bar.com ...

The containers being proxied must expose the port to be proxied, either by using the EXPOSE directive in their Dockerfile or by using the --expose flag to docker run or docker create. See nginx-proxy for more informations. To generate automatically Let's Encrypt certificates see next section.

Separate Containers (recommended method)

nginx proxy can also be run as two separate containers using the jwilder/docker-gen image and the official nginx image.

You may want to do this to prevent having the docker socket bound to a publicly exposed container service.

To run nginx proxy as a separate container you'll need to have nginx.tmpl on your host system and set the NGIX_DOCKER_GEN_CONTAINERenvironment variable to the name or id of the docker-gen container.

• First start nginx (official image) with volumes:

$ docker run -d -p 80:80 -p 443:443 \
    --name nginx \
    -v /etc/nginx/conf.d  \
    -v /etc/nginx/vhost.d \
    -v /usr/share/nginx/html \
    -v /path/to/certs:/etc/nginx/certs:ro \
    nginx

• Second start the docker-gen container with the shared volumes and the template file:

$ docker run -d \
    --name nginx-gen \
    --volumes-from nginx \
    -v /path/to/nginx.tmpl:/etc/docker-gen/templates/nginx.tmpl:ro \
    -v /var/run/docker.sock:/tmp/docker.sock:ro \
    jwilder/docker-gen \
    -notify-sighup nginx -watch -only-exposed -wait 5s:30s /etc/docker-gen/templates/nginx.tmpl /etc/nginx/conf.d/default.conf

• Then start this container (NGINX_DOCKER_GEN_CONTAINER variable must contain the docker-gen container name or id):

$ docker run -d \
    -e NGINX_DOCKER_GEN_CONTAINER=nginx-gen \
    --volumes-from nginx \
    -v /path/to/certs:/etc/nginx/certs:rw \
    -v /var/run/docker.sock:/var/run/docker.sock:ro \
    jrcs/letsencrypt-nginx-proxy-companion

Then start any containers to be proxied as described previously.

Let's Encrypt

To use the Let's Encrypt service to automatically create a valid certificate for virtual host(s).

Set the following environment variables to enable Let's Encrypt support for a container being proxied.

• LETSENCRYPT_HOST
• LETSENCRYPT_EMAIL

The LETSENCRYPT_HOST variable most likely needs to be the same as the VIRTUAL_HOST variable and must be publicly reachable domains. Specify multiple hosts with a comma delimiter.

For example

$ docker run -d \
    -e VIRTUAL_HOST="foo.bar.com,bar.com" \
    -e LETSENCRYPT_HOST="foo.bar.com,bar.com" \
    -e LETSENCRYPT_EMAIL="foo@bar.com" ...

Automatic certificate renewal

Every hour (3600 seconds) the certificates are checked and every certificate that will expire in the next 30 days (90 days / 3) are renewed.

Optional container environment variables

Optional letsencrypt-nginx-proxy-companion container environment variables for custom configuration.

• ACME_CA_URI - Directory URI for the CA ACME API endpoint (default: https://acme-v01.api.letsencrypt.org/directory)

For example

$ docker run -d \
    -e ACME_CA_URI="https://acme-staging.api.letsencrypt.org/directory" \
    -v /path/to/certs:/etc/nginx/certs:rw \
    --volumes-from nginx-proxy \
    -v /var/run/docker.sock:/var/run/docker.sock:ro \
    jrcs/letsencrypt-nginx-proxy-companion

• DEBUG - Set it to true to enable debugging of the entrypoint script, which could help you pin point any configuration issues.

• NGINX_PROXY_CONTAINER- I for some reason you can't use the docker --volumes-from option, you can specify the name or id of the nginx-proxy container with this variable.