Revert "DOCS-16593-chunks-update BACKPORT" (#6029)

Author: jason-price-mongodb

source/reference/config-database.txt

@@ -164,7 +164,7 @@ to support sharding:
 
    .. data:: config.changelog.what
 
-      The type of change recorded. Possible values include:
+      Reflects the type of change recorded. Possible values include:
 
       - ``dropCollection``
       - ``dropCollection.start``
@@ -181,48 +181,38 @@ to support sharding:
 
    .. data:: config.changelog.details
 
-      A :term:`document` that contains additional details for
+      A :term:`document` that contains  additional details regarding
       the change. The structure of the :data:`~config.changelog.details`
       document depends on the type of change.
 
 .. data:: config.chunks
 
    .. include:: /includes/admonition-config-db-is-internal.rst
 
-   The :data:`config.chunks` collection stores a document for each
-   chunk in the cluster. The following example shows a document:
+   The :data:`~config.chunks` collection stores a document for each chunk in
+   the cluster.  Consider the following example of a document for a
+   chunk named ``mydb.foo-a_\"cat\"``:
 
    .. code-block:: javascript
 
       {
-         _id: ObjectId('65a954c0de11596e08e7c1dc'),
-         uuid: UUID('a4479215-a38d-478f-a82b-e5e95d455e55'),
-         min: { a: Long('121204345') },
-         max: { a: Long('993849349') },
-         shard: 'shard01',
-         lastmod: Timestamp({ t: 1, i: 0 }),
-         history: [
-            {
-               validAfter: Timestamp({ t: 1705596095, i: 14 }),
-               shard: 'shard01'
-            }
-         ]
+         "_id" : "mydb.foo-a_\"cat\"",
+         "lastmod" : Timestamp(2, 1), 
+         "uuid": "c025d039-e626-435e-b2d2-c1d436038041",
+         "min" : {
+               "animal" : "cat"
+         },
+         "max" : {
+               "animal" : "dog"
+         },
+         "shard" : "shard0004",
+         "history" : [ { "validAfter" : Timestamp(1569368571, 27), "shard" : "shard0004" } ] 
       }
 
-   In the document:
-
-   - ``_id`` is the chunk identifier.
-   - ``min`` and ``max`` are the range of values for the chunk's shard
-     key.
-   - ``shard`` is the name of the shard that stores the chunk in the
-     cluster.
-
-   .. tip::
-
-      To find the chunks in a collection, retrieve the collection's
-      ``uuid`` identifier from the :data:`config.collections`
-      collection. Then, use ``uuid`` to retrieve the matching document
-      with the same ``uuid`` from the ``config.chunks`` collection.
+   These documents store the range of values for the shard key that
+   describe the chunk in the ``min`` and ``max`` fields. Additionally
+   the ``shard`` field identifies the shard in the cluster that "owns"
+   the chunk.
 
 .. data:: config.collections
 
@@ -470,7 +460,7 @@ to support sharding:
    .. include:: /includes/admonition-config-db-is-internal.rst
 
    The :data:`~config.version` collection holds the current metadata version number. This
-   collection contains only one document. For example:
+   collection contains only one document.  For example:
 
    .. code-block:: javascript
 
@@ -488,7 +478,9 @@ to support sharding:
 Collections to Support Sessions
 -------------------------------
 
-The ``config`` database contains the
+.. versionadded:: 3.6
+
+Starting in MongoDB 3.6, the ``config`` database contains the
 *internal* collections to support :ref:`causally consistent sessions
 <sessions>` for standalones, replica sets, and sharded clusters and
 retryable writes and :doc:`transactions </core/transactions>` for