Add guide to using Compose in production

Signed-off-by: Aanand Prasad <aanand.prasad@gmail.com>

docs/mkdocs.yml

@@ -1,5 +1,6 @@
 
 - ['compose/index.md', 'User Guide', 'Docker Compose' ]
+- ['compose/production.md', 'User Guide', 'Using Compose in production' ]
 - ['compose/install.md', 'Installation', 'Docker Compose']
 - ['compose/cli.md', 'Reference', 'Compose command line']
 - ['compose/yml.md', 'Reference', 'Compose yml']

docs/production.md

@@ -0,0 +1,77 @@
+page_title: Using Compose in production
+page_description: Guide to using Docker Compose in production
+page_keywords: documentation, docs,  docker, compose, orchestration, containers, production
+
+
+## Using Compose in production
+
+While **Compose is not yet considered production-ready**, you can try using it
+for production deployments if you're feeling brave. Production-readiness is an
+active, ongoing project - see the
+[roadmap](https://github.com/docker/compose/blob/master/ROADMAP.md) for details
+on how it's coming along and what needs to be done.
+
+When deploying to production, you'll almost certainly want to make changes to
+your app configuration that are more appropriate to a live environment. This may
+include:
+
+- Removing any volume bindings for application code, so that code stays inside
+  the container and can't be changed from outside
+- Binding to different ports on the host
+- Setting environment variables differently (e.g. to decrease the verbosity of
+  logging, or to enable email sending)
+- Specifying a restart policy (e.g. `restart: always`) to avoid downtime
+- Adding extra services (e.g. a log aggregator)
+
+For this reason, you'll probably want to define a separate Compose file, say
+`production.yml`, which specifies production-appropriate configuration.
+
+<!-- TODO: uncomment when the `extends` guide is merged
+> **Note:** The [extends](extends.md) keyword is useful for maintaining multiple
+> Compose files which re-use common services without having to manually copy and
+> paste.
+-->
+
+Once you've got an alternate configuration file, you can make Compose use it
+by setting the `COMPOSE_FILE` environment variable:
+
+    $ COMPOSE_FILE=production.yml
+    $ docker-compose up -d
+
+> **Note:** You can also use the file for a one-off command without setting
+> an environment variable by passing the `-f` flag, e.g.
+> `docker-compose -f production.yml up -d`.
+
+### Deploying changes
+
+When you make changes to your app code, you'll need to rebuild your image and
+recreate your app containers. If the service you want to redeploy is called
+`web`, this will look like:
+
+    $ docker-compose build web
+    $ docker-compose up --no-deps -d web
+
+This will first rebuild the image for `web` and then stop, destroy and recreate
+*just* the `web` service. The `--no-deps` flag prevents Compose from also
+recreating any services which `web` depends on.
+
+### Run Compose on a single server
+
+You can use Compose to deploy an app to a remote Docker host by setting the
+`DOCKER_HOST`, `DOCKER_TLS_VERIFY` and `DOCKER_CERT_PATH` environment variables
+appropriately. [Docker Machine](https://docs.docker.com/machine) makes managing
+local and remote Docker hosts very easy, and is recommended even if you're not
+deploying remotely.
+
+Once you've set up your environment variables, all the normal `docker-compose`
+commands will work with no extra configuration.
+
+### Run Compose on a Swarm cluster
+
+[Docker Swarm](https://docs.docker.com/swarm), a Docker-native clustering
+system, exposes the same API as a single Docker host, which means you can use
+Compose against a Swarm instance and run your apps across multiple hosts.
+
+Compose/Swarm integration is still in the experimental stage, and Swarm is still
+in beta, but if you're interested to try it out, check out the
+[integration guide](https://github.com/docker/compose/blob/master/SWARM.md).