Dokku uses nginx as its server for routing requests to specific applications. By default, access and error logs are written for each app to `/var/log/nginx/${APP}-access.log` and `/var/log/nginx/${APP}-error.log` respectively
Dokku uses a templating library by the name of [sigil](https://github.com/gliderlabs/sigil) to generate nginx configuration for each app. You may also provide a custom template for your application as follows:
> When using a custom `nginx.conf.sigil` file, depending upon your application configuration, you *may* be exposing the file externally. As this file is extracted before the container is run, you can, safely delete it in a custom `entrypoint.sh` configured in a Dockerfile `ENTRYPOINT`.
> The default template is available [here](https://github.com/dokku/dokku/blob/master/plugins/nginx-vhosts/templates/nginx.conf.sigil), and can be used as a guide for your own, custom `nginx.conf.sigil` file. Please refer to the appropriate template file version for your Dokku version.
### Available template variables
```
{{ .APP }} Application name
{{ .APP_SSL_PATH }} Path to SSL certificate and key
{{ .DOKKU_ROOT }} Global Dokku root directory (ex: app dir would be `{{ .DOKKU_ROOT }}/{{ .APP }}`)
{{ .DOKKU_APP_LISTENERS }} List of IP:PORT pairs of app containers
{{ .PROXY_PORT_MAP }} List of port mappings (same as `DOKKU_PROXY_PORT_MAP` config var)
{{ .PROXY_UPSTREAM_PORTS }} List of configured upstream ports (derived from `DOKKU_PROXY_PORT_MAP` config var)
{{ .RAW_TCP_PORTS }} List of exposed tcp ports as defined by Dockerfile `EXPOSE` directive (**Dockerfile apps only**)
{{ .SSL_INUSE }} Boolean set when an app is SSL-enabled
{{ .SSL_SERVER_NAME }} List of SSL VHOSTS
```
> Note: Application config variables are available for use in custom templates. To do so, use the form of `{{ var "FOO" }}` to access a variable named `FOO`.
The example above uses additional configuration files directly on the Dokku host. Unlike the `nginx.conf.sigil` file, these additional files will not be copied over from your application repo, and thus need to be placed in the `/home/dokku/node-js-app/nginx.conf.d/` directory manually.
For PHP Buildpack users, you will also need to provide a `Procfile` and an accompanying `nginx.conf` file to customize the nginx config *within* the container. The following are example contents for your `Procfile`