DOCSP-31324: keepalive settings removed + defaults (#738)

* DOCSP-31324: keepalive settings removed + defaults

* MW PR fixes 1

Author: rustagir

source/faq.txt

@@ -238,32 +238,50 @@ to an operation that returns a ``Cursor``:
 .. literalinclude:: /code-snippets/faq/maxTimeMS-example.js
   :language: javascript
 
-What Does the "keepAlive" Setting Do?
----------------------------------------
+.. _node-faq-keepalive:
 
-``keepAlive`` is a ``connection-setting`` that sets the number of
-milliseconds to wait before initiating a :wikipedia:`TLS keepAlive
-<Keepalive#TCP_keepalive>` on a TCP Socket. The ``keepAlive`` option
-will keep a socket alive by sending periodic probes to MongoDB. However,
-this only works if the operating system supports ``SO_KEEPALIVE``\ .
+What Does the keepAlive Option Do?
+----------------------------------
 
-This setting is deprecated in v5.3 of the {+driver-short+} and later.
+The ``keepAlive`` connection option specifies whether to enable
+:wikipedia:`Transmission Control Protocol (TCP) keepalives
+<Keepalive#TCP_keepalive>` on a TCP socket. If you enable keepalives,
+the driver checks whether the connection is active by sending periodic pings
+to your MongoDB deployment. This functionality only works if your
+operating system supports the ``SO_KEEPALIVE`` socket option.
+
+The ``keepAliveInitialDelay`` option specifies the number of
+milliseconds that the driver waits before initiating a keepalive.
+
+The 5.3 driver version release deprecated these options. Starting in
+version 6.0 of the driver, the ``keepAlive`` option is permanently set
+to ``true``, and the ``keepAliveInitialDelay`` is set to 300000
+milliseconds (300 seconds).
 
 .. warning::
-    If a firewall ignores or drops the ``keepAlive`` packets this may not work
+   
+   If your firewall ignores or drops the keepalive messages, you might
+   not be able to identify dropped connections.
 
 What Can I Do If I'm Experiencing Unexpected Network Behavior?
 --------------------------------------------------------------
-Internal firewalls that exist between application servers and MongoDB
-are often misconfigured and are overly aggressive in their removal of
-socket connections.
 
-If you experience unexpected network behavior, here
-are some things to check:
+You might experience unexpected network behavior if the firewall between
+your application and MongoDB is misconfigured. These firewalls can be
+overly aggressive in their removal of connections, which can lead to
+unexpected errors.
+
+Confirm that your firewall exhibits the following behavior:
 
-#. The firewall should send a ``FIN packet`` when closing a socket,
-   allowing the driver to detect that the socket is closed.
-#. The firewall should allow ``keepAlive`` probes.
+- The firewall sends a ``FIN`` packet when closing a connection,
+  informing the driver that the socket is closed.
+
+- The firewall allows keepalive messages.
+
+.. tip::
+   
+   To learn more about keepalive messages, see the :ref:`What Does the
+   keepAlive Option Do? <node-faq-keepalive>` FAQ entry.
 
 How Can I Prevent a Slow Operation From Delaying Other Operations?
 ------------------------------------------------------------------

source/upgrade.txt

@@ -70,6 +70,10 @@ Version 6.x Breaking Changes
   ``tlsCertificateKeyFile`` connection options when you call the
   ``MongoClient.connect()`` method, not when you create the
   ``MongoClient`` instance.
+- The driver removes the ``keepAlive`` and ``keepAliveInitialDelay`` connection
+  options. The value of ``keepAlive`` is permanently set to ``true`` and the
+  value of ``keepAliveInitialDelay`` is set to 300000 milliseconds (300
+  seconds).
 - The ``Db.command()`` method accepts only options that are not related
   to a specific command. To learn more about these options, see the  
   :ref:`Command Options <node-command-options>` section of the Run a

source/whats-new.txt

@@ -88,10 +88,10 @@ The {+driver-short+} v6.0 release includes the following features:
    object or set the ``tls``-prefixed options in your
    ``MongoClientOptions`` instance. To learn more, see :ref:`node-connect-tls`.
 
-- Removes support for the ``addUser()`` helper command. Use the
+- Removal of support for the ``addUser()`` helper command. Use the
   :manual:`createUser </reference/command/createUser>` MongoDB Shell command instead.
 
-- Removes support for the ``collStats`` operation. Use the
+- Removal of support for the ``collStats`` operation. Use the
   :manual:`$collStats </reference/operator/aggregation/collStats>` aggregation operator
   instead.
 
@@ -110,6 +110,15 @@ The {+driver-short+} v6.0 release includes the following features:
   the ``MongoClient.connect()`` method, not when you create a
   ``MongoClient`` instance.
 
+- Removal of the ``keepAlive`` and ``keepAliveInitialDelay`` connection
+  options. The value of ``keepAlive`` is permanently set to ``true`` and the
+  value of ``keepAliveInitialDelay`` is set to 300000 milliseconds (300
+  seconds).
+  
+  To learn how to set keepalive settings at a system level,
+  see the :manual:`Does TCP keepalive time affect MongoDB Deployments? </faq/diagnostics/#does-tcp-keepalive-time-affect-mongodb-deployments->`
+  FAQ entry in the Server manual.
+
 - Removes the following options for the ``Db.command()`` method:
 
   - ``willRetryWrite``