_application_container_config.html.md.erb

1. Select **Application Containers**.

	<%= image_tag("../images/er-config-app-containers.png") %>

1. The **Enable Custom Buildpacks** checkbox governs the ability to pass a custom buildpack URL to the `-b` option of the `cf push` command. By default, this ability is enabled, letting developers use custom buildpacks when deploying apps. Disable this option by disabling the checkbox. For more information about custom buildpacks, refer to the [buildpacks](../buildpacks/) section of the PCF documentation.

1. The **Allow SSH access to app containers** checkbox controls SSH access to application instances. Enable the checkbox to permit SSH access across your deployment, and disable it to prevent all SSH access. See the [Application SSH Overview](../devguide/deploy-apps/app-ssh-overview.html) topic for information about SSH access permissions at the space and app scope.

1. If you want enable SSH access for new apps by default in spaces that allow SSH, select **Enable SSH when an app is created**. If you deselect the checkbox, developers can still enable SSH after pushing their apps by running `cf enable-ssh APP-NAME`.

1. You can configure Elastic Runtime to run app instances in Docker containers by supplying their IP address range(s) in the **Private Docker Insecure Registry Whitelist** textbox. See the [Using Docker Registries](../opsguide/docker-registry.html) topic for more information.

1. By default, containers use the same DNS servers as the host. If you want to override the DNS servers to be used in containers, enter a comma-separated list of servers in **DNS Servers**. 

1. Select your preference for **Docker Images Disk-Cleanup Scheduling on Cell VMs**. If you choose **Clean up disk-space once threshold is reached**, enter a **Threshold of Disk-Used** in megabytes. For more information about the configuration options and how to configure a threshold, see [Configuring Docker Images Disk-Cleanup Scheduling](../opsguide/config-cell-cleanup.html). 

1. Optionally, enter a number in the **Max Inflight Container Starts** textbox. This number configures the maximum number of started instances across your deployment's Diego Cells. For more information about this feature, see [Setting a Maximum Number of Started Containers](../adminguide/max-container-starts.html).

1. Click **Save**.