DOC-12487 Maintain durable writes

modules/introduction/partials/new-features-80.adoc

@@ -108,6 +108,23 @@ and limits the number of metrics to 100.
 Additional information sent by clients at connection time can be found in the logs.
 
 
+[[new-feature-800-maintain-durable-writes]]
+https://jira.issues.couchbase.com/browse/MB-43068[MB-43068] OOptionally Maintain Durable Write Availability Without Majority After Failover::
+You can enable a cluster-level option named `durabilityImpossibleFallback` that allows durable writes to succeed even when they cannot meet their majority requirements.
+This option is off by default.
+Use this setting to allow clients to continue to perform successful durable writes when nodes are unavailable due to failovers.  
+For example, suppose you have a bucket with a single replica that clients write to using durable writes.
+You can enable this option while you're performing an upgrade using the graceful failover followed by a delta recovery method.
+Without this option, the client's durable writes fail until the nodes finish recovery, disrupting your applications.
+When you finish the upgrade, turn off this option to restore the normal durability requirements.
+
++
+include::learn:partial$maintain-durability-warning.adoc[]
+
++ 
+See xref:learn:data/durability.adoc#maintaining-durable-writes[Maintaining Durable Writes During Single Replica Failovers] for more information about this feature.
+
+
 [#section-new-feature-800-XDCR]
 === XDCR
 https://jira.issues.couchbase.com/browse/MB-61048[MB-61048]::