[Backport v1.11] DOCSP-47219 Midsync Reads FAQ

source/faq.txt

@@ -26,20 +26,26 @@ following the steps in :ref:`c2c-reconfigure-mid-migration`.
 Can I perform reads or writes to my destination cluster while ``mongosync`` is syncing?
 ---------------------------------------------------------------------------------------
 
-You can perform reads at any time during synchronization. 
-However, ``mongosync`` combines and reorders writes from the source to destination during synchronization, 
-and also temporarily modifies various collection characteristics. 
-As a result, the destination is not guaranteed to match the source at any point in time when the sync is running. 
-For consistent reads, wait for the migration to :ref:`c2c-api-commit`. To learn more, see :ref:`mongosync-considerations`. 
-
-Performing writes to your destination cluster during synchronization results in undefined behavior. 
-``mongosync`` blocks writes on the destination cluster by default. To learn
-more about write-blocking, see :ref:`c2c-write-blocking` and :ref:`c2c-api-start`.
-
-Upon commit, it is only safe to write to the destination cluster when ``canWrite`` is ``true``. 
-To check the value of ``canWrite``, run the :ref:`c2c-api-progress` endpoint.
-
-To learn more about permissable reads and writes during synchronization, see :ref:`c2c-reads-and-writes`. 
+``mongosync`` :ref:`combines and reorders <c2c-behavior-consistency>` writes 
+from the source to destination during synchronization, and 
+:ref:`temporarily modifies <c2c-behavior-temporary-changes>` collection 
+characteristics. As a result, ``mongosync`` can't guarantee that the destination 
+matches the source, including a stale version of the source, at any point in 
+time when the sync is running, even if the sync is paused. To safely accept 
+traffic to the destination cluster, wait for the migration to 
+:ref:`c2c-api-commit`. To learn more, see :ref:`mongosync-considerations`. 
+
+Performing writes to your destination cluster during synchronization results in 
+undefined behavior. ``mongosync`` blocks writes on the destination cluster by 
+default. To learn more about write-blocking, see :ref:`c2c-write-blocking` and 
+:ref:`c2c-api-start`.
+
+Upon commit, it is only safe to write to the destination cluster when 
+``canWrite`` is ``true``. To check the value of ``canWrite``, run the 
+:ref:`c2c-api-progress` endpoint.
+
+To learn more about permissable reads and writes during synchronization, see 
+:ref:`c2c-reads-and-writes`. 
 
 .. note::
 

source/reference/mongosync/mongosync-behavior.txt

@@ -232,6 +232,8 @@ snapshot of the source data. To learn more, see :ref:`c2c-behavior-consistency`.
    Otherwise, start a new continuous sync operation by using a new empty 
    destination cluster. 
 
+.. _c2c-behavior-temporary-changes:
+
 Temporary Changes to Collection Characteristics
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~