Update healthcheck doc for R4

Issue-ID: DCAEGEN2-1506
Change-Id: I241b19ca3ee6474afce9eeec28b4b989608f061b
Signed-off-by: Jack Lucas <jflucas@research.att.com>
diff --git a/docs/sections/healthcheck.rst b/docs/sections/healthcheck.rst
index 57266bb..d9b5e1f 100644
--- a/docs/sections/healthcheck.rst
+++ b/docs/sections/healthcheck.rst
@@ -1,73 +1,108 @@
 .. This work is licensed under a Creative Commons Attribution 4.0 International License.
 .. http://creativecommons.org/licenses/by/4.0
 
-HealthCheck
-===========
-
-DCAE Healthcheck .
+DCAE Health Check
+=================
 
 OOM Deployment
 --------------
+In OOM deployments, DCAE healthchecks are performed by a separate service--dcae-healthcheck.
+This service is packaged into a Docker image (``onap/org.onap.dcaegen2.deployments.healthcheck-container``),
+which is built in the ``healthcheck-container`` module in the ``dcaegen2/deployments`` repository.
 
-    In OOM deployments DCAE healthcheck are reported by separate  service - dcae-healthcheck; this is deployment of org.onap.dcaegen2.deployments.healthcheck-container which is built from dcaegen2/deployment repo - healthcheck-container module. The container includes list of deployments done in DCAE  (both via helm charts and Cloudify) for which periodic health check is performed. For helm deployed component - servicename defined is charts are used and for cloudify, the deployments identified in bootstrap are prefixed with release name. The container itself is deployed via helm charts (oom/kubernetes/dcaegen2/charts/dcae-healthcheck). This polls the deployments specified periodically and reports the status. The service can be queried for status as below. 
-    
-curl dcae-healthcheck    
-.. code-block:: json    
+The service is deployed with a Helm chart (``oom/kubernetes/dcaegen2/charts/dcae-healthcheck``)
+when DCAE is deployed using OOM.
 
-         
-         
-         {
-            "type": "summary",
-            "count": 11,
-            "ready": 11,
-            "items": [{
-                "name": "dev-dcaegen2-dcae-cloudify-manager",
-                "ready": 1,
-                "unavailable": 0
-            }, {
-                "name": "dep-config-binding-service",
-                "ready": 1,
-                "unavailable": 0
-            }, {
-                "name": "dep-deployment-handler",
-                "ready": 1,
-                "unavailable": 0
-            }, {
-                "name": "dep-inventory",
-                "ready": 1,
-                "unavailable": 0
-            }, {
-                "name": "dep-service-change-handler",
-                "ready": 1,
-                "unavailable": 0
-            }, {
-                "name": "dep-policy-handler",
-                "ready": 1,
-                "unavailable": 0
-            }, {
-                "name": "dep-dcae-ves-collector",
-                "ready": 1,
-                "unavailable": 0
-            }, {
-                "name": "dep-dcae-tca-analytics",
-                "ready": 1,
-                "unavailable": 0
-            }, {
-                "name": "dep-dcae-prh",
-                "ready": 1,
-                "unavailable": 0
-            }, {
-                "name": "dep-dcae-hv-ves-collector",
-                "ready": 1,
-                "unavailable": 0
-            }, {
-                "name": "dep-dcae-datafile-collector",
-                "ready": 1,
-                "unavailable": 0
-            }]
+The dcae-healthcheck container runs a service that exposes a simple Web API.  In response to
+request, the service checks Kubernetes to verify that all of the expected
+DCAE platform and service components are in a ready state.  The service
+has a fixed list of platform and service components that are normally deployed when DCAE is
+first installed, including components deployed with Helm charts and
+components deployed using Cloudify blueprints.   In addition, beginning with
+the Dublin release, the healthcheck
+service tracks and checks components that are deployed dynamically using Cloudify
+blueprints after the initial DCAE installation.
+
+The healthcheck service is exposed as a Kubernetes ClusterIP Service named
+`dcae-healthcheck`.   The service can be queried for status as shown below.
+
+.. code-block::
+
+   $ curl dcae-healthcheck
+   {
+     "type": "summary",
+     "count": 14,
+     "ready": 14,
+     "items": [
+        {
+          "name": "dev-dcaegen2-dcae-cloudify-manager",
+          "ready": 1,
+          "unavailable": 0
+        },
+        {
+          "name": "dev-dcaegen2-dcae-config-binding-service",
+          "ready": 1,
+          "unavailable": 0
+        },
+        {
+          "name": "dev-dcaegen2-dcae-inventory-api",
+          "ready": 1,
+          "unavailable": 0
+        },
+        {
+          "name": "dev-dcaegen2-dcae-servicechange-handler",
+          "ready": 1,
+          "unavailable": 0
+        },
+        {
+          "name": "dev-dcaegen2-dcae-deployment-handler",
+          "ready": 1,
+          "unavailable": 0
+        },
+        {
+          "name": "dev-dcaegen2-dcae-policy-handler",
+          "ready": 1,
+          "unavailable": 0
+        },
+        {
+          "name": "dep-dcae-ves-collector",
+          "ready": 1,
+          "unavailable": 0
+        },
+        {
+          "name": "dep-dcae-tca-analytics",
+          "ready": 1,
+          "unavailable": 0
+        },
+        {
+          "name": "dep-dcae-prh",
+          "ready": 1,
+          "unavailable": 0
+        },
+        {
+          "name": "dep-dcae-hv-ves-collector",
+          "ready": 1,
+          "unavailable": 0
+        },
+        {
+          "name": "dep-dcae-dashboard",
+          "ready": 1,
+          "unavailable": 0
+        },
+        {
+          "name": "dep-dcae-snmptrap-collector",
+          "ready": 1,
+          "unavailable": 0
+        },
+        {
+          "name": "dep-holmes-engine-mgmt",
+          "ready": 1,
+          "unavailable": 0
+        },
+        {
+          "name": "dep-holmes-rule-mgmt",
+          "ready": 1,
+          "unavailable": 0
         }
-        
-        
-
-Heat Deployment
----------------
+      ]
+    }