3.2 rel notes, enableMajorityReadConcern

Author: kay-kim

source/release-notes/3.2.txt

@@ -185,8 +185,16 @@ be rolled back. By default, MongoDB uses a ``readConcern`` of
 ``"local"`` which does not guarantee that the read data would not be
 rolled back.
 
+Considerations
+~~~~~~~~~~~~~~
+
 ``readConcern`` requires MongoDB drivers updated for 3.2.
 
+To use ``readConcern`` level of ``"majority"``, you must start the
+:program:`mongod` instances with ``--enableMajorityReadConcern``
+command line option or, if using a configuration file, the
+``replication.enableMajorityReadConcern`` setting.
+
 ``readConcern`` Option
 ~~~~~~~~~~~~~~~~~~~~~~