Add config network topic, incl. macvlan ui (#203)

* Draft of macvlan topic

* Add topic on config networks

* Incorporate feedback

datacenter/ucp/2.2/guides/admin/configure/use-node-local-network-in-swarm.md

@@ -0,0 +1,52 @@
+---
+title: Use a local node network in a swarm
+description: Learn how to use a local node network, like MAC VLAN, in a UCP swarm.
+keywords: ucp, network, macvlan
+---
+
+Docker Universal Control Plane can use your local networking drivers to
+orchestrate your swarm. You can create a *config* network, with a driver like
+MAC VLAN, and you use it like any other named network in UCP. If it's set up
+as attachable, you can attach containers.
+
+> Security
+>
+> Encrypting communication between containers on different nodes works only on
+> overlay networks. 
+
+## Use UCP to create node-specific networks
+
+Always use UCP to create node-specific networks. You can use the UCP web UI 
+or the CLI (with an admin bundle), but don't side-band to the Docker engines
+directly, otherwise your networks may be mislabelled and become inaccessible.
+
+When you create a config network *without* UCP, you `ssh` to each node in the
+swarm, and `docker network create --config-only ...` for each back-end network.
+Then, on a manager node, you create the central network once, with the
+`--config-from` option.
+
+Don't do this when you're using UCP. You must create the node-specific networks
+through the UCP web UI or CLI. In either case, you should create all of the
+config-only networks before you create the config-from network.
+
+## Create a MAC VLAN network
+
+1. Log in as an administrator.
+2. Navigate to **Networks** and click **Create Network**.
+3. Name the network "macvlan".
+4. In the **Driver** dropdown,. select **Macvlan**.
+5. In the **Macvlan Configure** section, select  the configuration option.
+
+   - **Config Only**: Prefix the `config-only` network name with a node hostname
+   prefix, like `node1/my-cfg-network`, `node2/my-cfg-network`, *etc*. This is
+   necessary to ensure that the access labels are applied consistently to all of
+   the back-end config-only networks. UCP routes the config-only network creation
+   to the appropriate node based on the node hostname prefix. All config-only
+   networks with the same name must belong in the same collection, or UCP returns
+   an error. Leaving the access label empty puts the network in the admin's default
+   collection, which is `/` in a new UCP installation.
+   - **Config From**: Create the network from a Docker config. Don't set up an
+   access label for the config-from network. The labels of the network and its
+   collection placement are inherited from the related config-only networks.
+
+6. Click **Create** to create the network.