nginx-proxy sets up a container running nginx and [docker-gen][1]. docker-gen generates reverse proxy configs for nginx and reloads nginx when containers are started and stopped.
The containers being proxied must [expose](https://docs.docker.com/engine/reference/builder/#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`.
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.
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.
If you need to support multiple 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.
### Wildcard Hosts
You can also use wildcards at the beginning and the end of host name, like `*.bar.com` or `foo.bar.*`. Or even a regular expression, which can be very useful in conjunction with a wildcard DNS service like [xip.io](http://xip.io), using `~^foo\.bar\..*\.xip\.io` will match `foo.bar.127.0.0.1.xip.io`, `foo.bar.10.0.2.2.xip.io` and all other given IPs. More information about this topic can be found in the nginx documentation about [`server_names`](http://nginx.org/en/docs/http/server_names.html).
With the addition of [overlay networking](https://docs.docker.com/engine/userguide/networking/get-started-overlay/) in Docker 1.9, your `nginx-proxy` container may need to connect to backend containers on multiple networks. By default, if you don't pass the `--net` flag when your `nginx-proxy` container is created, it will only be attached to the default `bridge` network. This means that it will not be able to connect to containers on networks other than `bridge`.
If you want your `nginx-proxy` container to be attached to a different network, you must pass the `--net=my-network` option in your `docker create` or `docker run` command. At the time of this writing, only a single network can be specified at container creation time. To attach to other networks, you can use the `docker network connect` command after your container is created:
In this example, the `my-nginx-proxy` container will be connected to `my-network` and `my-other-network` and will be able to proxy to other containers attached to those networks.
To run nginx proxy as a separate container you'll need to have [nginx.tmpl](https://github.com/jwilder/nginx-proxy/blob/master/nginx.tmpl) on your host system.
[letsencrypt-nginx-proxy-companion](https://github.com/JrCs/docker-letsencrypt-nginx-proxy-companion)is a lightweight companion container for the nginx-proxy. It allow the creation/renewal of Let's Encrypt certificates automatically.
You'll need apache2-utils on the machine where you plan to create the htpasswd file. Follow these [instructions](http://httpd.apache.org/docs/2.2/programs/htpasswd.html)
If you need to configure Nginx beyond what is possible using environment variables, you can provide custom configuration files on either a proxy-wide or per-`VIRTUAL_HOST` basis.
If you want to replace the default proxy settings for the nginx container, add a configuration file at `/etc/nginx/proxy.conf`. A file with the default settings would
***NOTE***: If you provide this file it will replace the defaults; you may want to check the .tmpl file to make sure you have all of the needed options.
***NOTE***: The default configuration blocks the `Proxy` HTTP request header from being sent to downstream servers. This prevents attackers from using the so-called [httpoxy attack](http://httpoxy.org). There is no legitimate reason for a client to send this header, and there are many vulnerable languages / platforms (`CVE-2016-5385`, `CVE-2016-5386`, `CVE-2016-5387`, `CVE-2016-5388`, `CVE-2016-1000109`, `CVE-2016-1000110`, `CERT-VU#797896`).
To add settings on a per-`VIRTUAL_HOST` basis, add your configuration file under `/etc/nginx/vhost.d`. Unlike in the proxy-wide case, which allows multiple config files with any name ending in `.conf`, the per-`VIRTUAL_HOST` file must be named exactly after the `VIRTUAL_HOST`.
In order to allow virtual hosts to be dynamically configured as backends are added and removed, it makes the most sense to mount an external directory as `/etc/nginx/vhost.d` as opposed to using derived images or mounting individual configuration files.
If you are using multiple hostnames for a single container (e.g. `VIRTUAL_HOST=example.com,www.example.com`), the virtual host configuration file must exist for each hostname. If you would like to use the same configuration for multiple virtual host names, you can use a symlink:
If you want most of your virtual hosts to use a default single configuration and then override on a few specific ones, add those settings to the `/etc/nginx/vhost.d/default` file. This file
will be used on any virtual host which does not have a `/etc/nginx/vhost.d/{VIRTUAL_HOST}` file associated with it.
To add settings to the "location" block on a per-`VIRTUAL_HOST` basis, add your configuration file under `/etc/nginx/vhost.d`
just like the previous section except with the suffix `_location`.
For example, if you have a virtual host named `app.example.com` and you have configured a proxy_cache `my-cache` in another custom file, you could tell it to use a proxy cache as follows:
If you are using multiple hostnames for a single container (e.g. `VIRTUAL_HOST=example.com,www.example.com`), the virtual host configuration file must exist for each hostname. If you would like to use the same configuration for multiple virtual host names, you can use a symlink:
If you want most of your virtual hosts to use a default single `location` block configuration and then override on a few specific ones, add those settings to the `/etc/nginx/vhost.d/default_location` file. This file
will be used on any virtual host which does not have a `/etc/nginx/vhost.d/{VIRTUAL_HOST}` file associated with it.