DOCS-11169: Small fixes to oplogSize, oplogSizeMB, replica-set-oplog.txt

Author: ravindk89

source/core/replica-set-oplog.txt

@@ -96,11 +96,11 @@ replica sets have much lower operation volumes, and their oplogs can
 hold much higher numbers of operations.
 
 Before :program:`mongod` creates an oplog, you can specify its size with
-the :setting:`~replication.oplogSizeMB` option. Once you have started  a
+the :setting:`~replication.oplogSizeMB` option. Once you have started a
 replica set member for the first time, use the
-:dbcommand:`replSetResizeOplog` to change the oplog size.
-:dbcommand:`replSetResizeOplog` enables you to resize the oplog
-dynamically without restarting the :program:`mongod` process.
+:dbcommand:`replSetResizeOplog` administrative command to change the 
+oplog size. :dbcommand:`replSetResizeOplog` enables you to resize the 
+oplog dynamically without restarting the :program:`mongod` process.
 
 Workloads that Might Require a Larger Oplog Size
 ------------------------------------------------

source/includes/options-mongod.yaml

@@ -1004,9 +1004,14 @@ description: |
   {{intro}} maximum size in megabytes for the replication operation log
   (i.e., the :term:`oplog`). The {{program}} process creates an
   :term:`oplog` based on the maximum amount of space available. For 64-bit
-  systems, the oplog is typically 5% of available disk space. Once the
-  {{program}} has created the oplog for the first time, changing the
-  {{role}} option will not affect the size of the oplog.
+  systems, the oplog is typically 5% of available disk space. 
+
+  Once the {{program}} has created the oplog for the first time,
+  changing the {{role}} option will not affect the size of the oplog.
+  Use the :dbcommand:`replSetResizeOplog` administrative command to
+  change the oplog size of a running {{program}} replica set member.
+  :dbcommand:`replSetResizeOplog` enables you to resize the oplog
+  dynamically without restarting the :program:`mongod` process.
 
   See :ref:`replica-set-oplog-sizing` for more information.
 optional: true