Import Daemon Metrics from docker/docker for dockerd

_data/dockerd-cli/dockerd.yaml

@@ -985,6 +985,33 @@ long: |
   option on `docker create` and `docker run`, and takes precedence over
   the `--cgroup-parent` option on the daemon.
 
+  ## Daemon Metrics
+
+  The `--metrics-addr` option takes a TCP address to serve the metrics API. This
+  feature is still experimental, therefore, the daemon must be running in
+  experimental  mode for this feature to work.
+
+  To serve the metrics API on localhost:1337 you would specify
+  `--metrics-addr 127.0.0.1:1337` allowing you to make requests on the API at
+  `127.0.0.1:1337/metrics` to receive metrics in the
+  [prometheus](https://prometheus.io/docs/instrumenting/exposition_formats/)
+  format.
+
+  If you are running a prometheus server you can add this address to your scrape
+  configs to have prometheus collect metrics on Docker.  For more information on
+  prometheus you can view the website [here](https://prometheus.io/).
+
+  ```yml
+  scrape_configs:
+    - job_name: 'docker'
+      static_configs:
+        - targets: ['127.0.0.1:1337']
+  ```
+
+  Please note that this feature is still marked as experimental as metrics and
+  metric names could change while this feature is still in experimental. Please
+  provide feedback on what you would like to see collected in the API.
+
   ## Daemon configuration file
 
   The `--config-file` option allows you to set any configuration option
@@ -1327,6 +1354,8 @@ options:
 - option: max-concurrent-uploads
   default_value: 5
   description: Set the max concurrent uploads for each push
+- option: metrics-addr
+  description: Set address and port to serve the metrics api
 - option: mtu
   description: Set the containers network MTU
 - option: oom-score-adjust

_data/toc.yaml

@@ -440,7 +440,7 @@ toc:
   - path: /engine/reference/commandline/cli/
     title: Use the Docker command line
   - path: /engine/reference/commandline/dockerd/
-    title: Daemon CLI reference
+    title: Daemon CLI reference (dockerd)
   - sectiontitle: Engine CLI reference
     section:
     - path: /engine/reference/commandline/docker/