anchor.diff:  
   <strong><%= modified_date %></strong>
   
  -This topic provides information about how Docker works in Cloud Foundry and describes how to push an application with a Docker image.
  -For information about Diego, see the [Diego Architecture](../concepts/diego/diego-architecture.html) topic.
  +This topic describes how Cloud Foundry (CF) operators can enable CF developers to run their apps in Docker containers, and explains how Docker works in Cloud Foundry.
  +
  +For information about Diego, the Cloud Foundry component that manages application containers, see the [Diego Architecture](../concepts/diego/diego-architecture.html) topic.  For how CF developers push apps with Docker images, see [Push a Docker Image](../devguide/deploy-apps/push-docker.html).
  +
  +##<a id='enable'></a>Enable Docker
  +
  +The `cf push` command defaults to running apps in standard Cloud Foundry Linux containers, but Cloud Foundry can also deploy and manage apps running in Docker containers.
  +
  +To enable Docker support on their CF deployments, operators use the `diego_docker` feature flag. Docker support lets CF developers push apps to Docker containers by including the `--docker-image` option to `cf push` and supplying the location of the Docker image to create the containers from.
  +
  +To enable Docker support, run:
  +<pre class='terminal'>
  +$ cf enable-feature-flag diego_docker
  +</pre>
  +
  +To disable Docker support, run:
  +
  +<pre class='terminal'>
  +$ cf disable-feature-flag diego_docker
  +</pre>
  +
  +<p class='note'><strong>Note</strong>: Disabling the <code>diego_docker</code> feature flag stops all Docker-based apps in your deployment within a few convergence cycles, on the order of a minute.</p>
   
   <%= vars.docker_auth2 %>
   
  -In addition to the default Linux environment provided by Cloud Foundry, 
  -operators can specify a Docker image that provides the file system used by the 
  -container.
  -When pushing an app, you can specify the location of the Docker image you want 
  -to use.
  +See the [Push a Docker Image](../devguide/deploy-apps/push-docker.html) topic for how CF developers push apps with Docker images. 
  +
  +##<a id='contents'></a>Docker Image Contents
   
   A Docker image consists of a collection of layers.
   Each layer consists of one or both of the following:
  
positive.code: resource usage.
  These are common kernel resource isolation features used by all Linux 
  containers.
  
  Before Garden-runC creates a Linux container, it creates a file system that is 
  mounted as the root file system of the container.
  
negative.code: 
  ##<a id='create-container'></a>How Garden-runC Creates Containers##
  
  Diego currently uses Garden-runC to construct Linux containers.
  
  Both Docker and Garden-runC use libraries from the [Open Container Initiative (OCI)](https://www.opencontainers.org/) to build Linux containers.
  After creation, these containers use name space isolation, or *namespaces*, and 
  