/nginx-proxy

Automated nginx proxy for Docker containers using docker-gen

nginx-proxy sets up a container running nginx and docker-gen. docker-gen generate reverse proxy configs for nginx and reloads nginx when containers are started and stopped.

See Automated Nginx Reverse Proxy for Docker for why you might want to use this.

Usage

To run it:

$ docker run -d -p 80:80 -v /var/run/docker.sock:/tmp/docker.sock jwilder/nginx-proxy

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

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

Provided your DNS is setup to forward foo.bar.com to the a host running nginx-proxy, the request will be routed to a container with the VIRTUAL_HOST env var set.

Multiple Ports

If your container exposes multiple ports, nginx-proxy will default to the service running on port 80. If you need to specify a different port, you can set a VIRTUAL_PORT env var to select a different one. If your container only exposes one port and it has a VIRTUAL_HOST env var set, that port will be selected.

Multiple Hosts

If you need to support multipe virtual hosts for a container, you can separate each entry with commas. For example, foo.bar.com,baz.bar.com,bar.com and each host will be setup the same.

Separate Containers

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.

First start nginx with a volume:

$ docker run -d -p 80:80 --name nginx -v /tmp/nginx:/etc/nginx/conf.d -t nginx

Then start the docker-gen container with the shared volume and template:

$ docker run --volumes-from nginx \
    -v /var/run/docker.sock:/tmp/docker.sock \
    -v $(pwd):/etc/docker-gen/templates \
    -t docker-gen -notify-sighup nginx -watch -only-published /etc/docker-gen/templates/nginx.tmpl /etc/nginx/conf.d/default.conf

Finally, start your containers with VIRTUAL_HOST environment variables.

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

SSL Support

SSL is supported single host, wildcards and SNI certificates using naming conventions for certificates or optionally specify a cert name (for SNI) as an environment variable.

To enable SSL:

$ docker run -d -p 80:80 -p 443:443 -v /path/to/certs:/etc/nginx/certs -v /var/run/docker.sock:/tmp/docker.sock jwilder/nginx-proxy

The contents of /path/to/certs should contain the certificates and private keys for any virtual hosts in use. The certificate and keys should be named after the virtual host with a .crt and .key extension. For example, a container with VIRTUAL_HOST=foo.bar.com should have a foo.bar.com.crt and foo.bar.com.key file in the certs directory.

Wildcard Certificates

Wildcard certificates and keys should be name after the domain name with a .crt and .key extension. For example VIRTUAL_HOST=foo.bar.com would use cert name bar.com.crt and bar.com.key.

SNI

If your certificate(s) supports multiple domain names, you can start a container with CERT_NAME=<name> to identify the certificate to be used. For example, a certificate for *.foo.com and *.bar.com could be named shared.crt and shared.key. A container running with VIRTUAL_HOST=foo.bar.com and CERT_NAME=shared will then use this shared cert.

How SSL Support Works

The SSL cipher configuration is based on mozilla nginx intermediate profile which should provide compatibility with clients back to Firefox 1, Chrome 1, IE 7, Opera 5, Safari 1, Windows XP IE8, Android 2.3, Java 7. The configuration also enables HSTS, and SSL session caches.

The behavior for the proxy when port 80 and 443 are exposed is as follows:

  • If a container has a usable cert, port 80 will redirect to 443 for that container so that HTTPS is always preferred when available.
  • If the container does not have a usable cert, a 503 will be returned.

Note that in the latter case, a browser may get an connection error as no certificate is available to establish a connection. A self-signed or generic cert named default.crt and default.key will allow a client browser to make a SSL connection (likely w/ a warning) and subsequently receive a 503.