Adds required specs for geosharded clusters.

Author: erabil-mdb

source/cluster-config-file.txt

@@ -150,10 +150,45 @@ Optional and Conditional {+Cluster+} Settings
 ---------------------------------------------
 
 Your {+cluster+} configuration file may contain additional optional or
-conditional {+cluster+} settings. For a full list of available
+conditional {+cluster+} settings. If you selected a ``clusterType`` of ``GEOSHARDED``, you must specify these {+cluster+} settings either
+in the configuration file or as flags in the command:
+
+.. list-table:: 
+   :header-rows: 1 
+   :widths: 20 10 70 
+
+   * - Field 
+     - Type 
+     - Description 
+
+   * - ``replicationSpecs.``
+       ``numShards``
+     - string
+     - Positive integer that specifies the number of shards to deploy
+       in each specified zone. Provide this value if you set a
+       ``clusterType`` of ``SHARDED`` or ``GEOSHARDED``. Omit this
+       value if you selected a ``clusterType`` of ``REPLICASET``.
+
+       This API resource accepts ``1`` through ``50``, inclusive. This
+       parameter defaults to ``1``.
+
+       If you specify a ``numShards`` value of ``1`` and a
+       ``clusterType`` of ``SHARDED``, |service| deploys a single-shard
+       `sharded cluster <https://www.mongodb.com/docs/manual/reference/glossary/#std-term-sharded-cluster>`__.
+
+       Don't create a sharded cluster with a single shard for production environments. Single-shard sharded clusters don't provide the same benefits as multi-shard configurations.
+
+   * - ``replicationSpecs.``
+       ``zoneName``
+     - string
+     - Name for the zone in a :ref:`Global Cluster <global-clusters>`. 
+       Provide this value if you set ``clusterType`` to ``GEOSHARDED``.
+
+For a full list of available
 settings, see the API documentation for 
-:atlas:`Create One Multi-Cloud Cluster from One Project 
-</reference/api-resources-spec/#operation/createOneAdvancedClusterFromOneProject>`.
+:oas-atlas-op:`Create One Cluster </createOneCluster>` and 
+:oas-atlas-op:`Create One Multi-Cloud Cluster from One Project 
+</createCluster>`.
 
 .. _example-cluster-config-file: