Add warning when updating search.idle.after with Segment Replication …

…enabled.

Signed-off-by: Marc Handalian <handalm@amazon.com>

server/src/main/java/org/opensearch/index/IndexSettings.java

@@ -918,6 +918,9 @@ private void setSearchSegmentOrderReversed(boolean reversed) {
     }
 
     private void setSearchIdleAfter(TimeValue searchIdleAfter) {
+        if (this.replicationType == ReplicationType.SEGMENT && this.getNumberOfReplicas() > 0) {
+            logger.warn("Search idle is disabled for indices with replicas using the Segment Replication strategy");
+        }
         this.searchIdleAfter = searchIdleAfter;
     }