add ipv6 info to faq (#425)

* add ipv6 info to faq

* wording

* grammar

* suggestions

Author: terakilobyte

source/faq.txt

@@ -12,6 +12,35 @@ Frequently Asked Questions
    :depth: 2
    :class: singlecol
 
+How to fix a "MongoServerSelectionError: connect ECONNREFUSED ::1:27017" error?
+-------------------------------------------------------------------------------
+
+Beginning with version 17, Node.js defaults to using ``IPV6``. You have a few
+options to resolve this error:
+
+- Start your ``mongod`` in ``IPV6`` mode with :manual:`the --ipv6 flag </reference/program/mongod/#std-option-mongod.--ipv6>`, or
+  setting the ``net.ipv6`` option to ``true`` :manual:`in your configuration file </reference/configuration-options/#mongodb-setting-net.ipv6>`.
+
+  .. code-block:: sh
+     :caption: Starting mongod with the --ipv6 flag
+
+     mongod --ipv6
+
+  .. code-block:: yaml
+     :caption: Setting the net.ipv6 option in the configuration file
+
+     net:
+       ipv6: true
+
+- Explicitly use ``IPV4`` by specifying ``family: 4`` as an
+  `option to your MongoClient <{+api+}/interfaces/MongoClientOptions.html#family>`__.
+
+  .. code-block:: js
+
+      const client = new MongoClient(uri, {
+        family: 4,
+      });
+
 
 What Is the Difference Between "connectTimeoutMS", "socketTimeoutMS" and "maxTimeMS"?
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