diff --git a/server/src/main/java/org/elasticsearch/index/store/FsDirectoryService.java b/server/src/main/java/org/elasticsearch/index/store/FsDirectoryService.java
index badf981803603..a8b50fcc53895 100644
--- a/server/src/main/java/org/elasticsearch/index/store/FsDirectoryService.java
+++ b/server/src/main/java/org/elasticsearch/index/store/FsDirectoryService.java
@@ -144,6 +144,7 @@ public IndexInput openInput(String name, IOContext context) throws IOException {
                 case "nvd":
                 case "dvd":
                 case "tim":
+                case "cfs":
                     // we need to do these checks on the outer directory since the inner doesn't know about pending deletes
                     ensureOpen();
                     ensureCanRead(name);