DOCSP 31207 Clarify mongosync reverse documentation unique index limitation (#181) (#197)

* DOCSP-32107 adding steps on resyncing all nodes

* DOCSP-32107 adding steps on resyncing all nodes

* DOCSP-32107 adding steps on resyncing all nodes

* DOCSP-32107 adding steps on resyncing all nodes

* DOCSP-31207 changing last sentence

* DOCSP-31207 changing last sentence

* DOCSP-31207 copy edits

* empty commit

* DOCSP-31207 tech edits

Author: ltran-mdb2

source/reference/api/reverse.txt

@@ -63,16 +63,26 @@ Clusters that began with MongoDB 4.2 or older and were since
 upgraded may include unique indexes that are not properly formatted.
 
 To correct indexes, you can :ref:`resync <resync-replica-member>` all nodes
-in the original source cluster.  If you don't want to resync the cluster, you
-can use the :method:`db.collection.validate` method on each collection to 
-determine whether it contains improperly formatted unique indexes.
+in the original source cluster.  To resync all nodes: 
 
-.. code-block:: javascript
+.. procedure::
+   :style: normal
 
-   db.<collection>.validate()
+   .. step:: Resync all secondaries, one by one. 
 
-If the method returns a warning about the unique index, you must
-resync all of the nodes in the original source cluster before reversing sync.
+      For a tutorial on resyncing nodes, see :ref:`Resync a Member of a
+      Replica Set <resync-replica-member>`. 
+
+   .. step:: Step down the primary node and step up one of the secondary nodes.
+   
+   .. step:: Resync the old primary node from the new primary node. 
+
+Alternatively, to avoid resyncing, you can use the
+:method:`db.collection.validate` method with ``full = false`` on each
+collection with unique indexes on all nodes to determine whether each
+collection contains improperly formatted unique indexes. If
+:method:`db.collection.validate` does not return a warning about a
+unique index, you can skip resyncing. 
 
 Request
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