Document how to install numerous Windows services

source/includes/options-mongod.exe.yaml

@@ -3,6 +3,11 @@ name: install
 directive: option
 description: |
   Installs {{program}} as a Windows Service and exits.
+
+  If needed, you can install services for multiple instances of
+  {{program}}. Install each service with a unique :option:`--serviceName`
+  and :option:`--serviceDisplayName`. Use multiple instances only when
+  sufficient system resources exist and your system design requires it.
 optional: true
 ---
 program: mongod.exe

source/includes/steps-configure-windows-service-for-mongodb.yaml

@@ -40,6 +40,13 @@ post: |
 
   If the :setting:`dbpath` directory does not exist, :program:`mongod.exe`
   will not start. The default value for :setting:`dbpath` is ``\data\db``.
+
+  If needed, you can install services for multiple instances of
+  :program:`mongod.exe` or :program:`mongos.exe`. Install each service
+  with a unique :option:`--serviceName <mongod.exe --serviceName>` and
+  :option:`--serviceDisplayName <mongod.exe --serviceDisplayName>`. Use
+  multiple instances only when sufficient system resources exist and your
+  system design requires it.
 ---
 title: Stop or remove the MongoDB service as needed.
 stepnum: 3