diff --git a/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/resolver/MountTableResolver.java b/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/resolver/MountTableResolver.java
index 893d70b117ab4..fc17d18902163 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/resolver/MountTableResolver.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/resolver/MountTableResolver.java
@@ -113,7 +113,7 @@ public class MountTableResolver
   private final Lock writeLock = readWriteLock.writeLock();
 
   /** Trash Current matching pattern. */
-  private static final String TRASH_PATTERN = "/(Current|[0-9]+)";
+  private static final String TRASH_PATTERN = "/(Current|[0-9]{12})";
 
   @VisibleForTesting
   public MountTableResolver(Configuration conf) {