diff --git a/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterRpcServer.java b/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterRpcServer.java
index 30c6cdcf2f16a..bc723cad66c14 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterRpcServer.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterRpcServer.java
@@ -78,6 +78,7 @@
 import org.apache.hadoop.hdfs.protocolPB.AsyncRpcProtocolPBUtil;
 import org.apache.hadoop.hdfs.server.federation.router.async.ApplyFunction;
 import org.apache.hadoop.hdfs.server.federation.router.async.AsyncCatchFunction;
+import org.apache.hadoop.hdfs.server.federation.router.async.CatchFunction;
 import org.apache.hadoop.thirdparty.com.google.common.cache.CacheBuilder;
 import org.apache.hadoop.thirdparty.com.google.common.cache.CacheLoader;
 import org.apache.hadoop.thirdparty.com.google.common.cache.LoadingCache;
@@ -832,7 +833,7 @@ <T> T invokeAtAvailableNsAsync(RemoteMethod method, Class<T> clazz)
           throw ioe;
         }
         nss.removeIf(n -> n.getNameserviceId().equals(nsId));
-        invokeOnNs(method, clazz, io, nss);
+        invokeOnNsAsync(method, clazz, io, nss);
       }, IOException.class);
     } else {
       // If not have default NS.
@@ -907,13 +908,14 @@ <T> T invokeOnNsAsync(RemoteMethod method, Class<T> clazz, IOException ioe,
         });
       });
 
-      asyncCatch((AsyncCatchFunction<T, IOException>)(ret, ex) -> {
+      asyncCatch((CatchFunction<T, IOException>)(ret, ex) -> {
         LOG.debug("Failed to invoke {} on namespace {}", method, nsId, ex);
         // Ignore the exception and try on other namespace, if the tried
         // namespace is unavailable, else throw the received exception.
         if (!clientProto.isUnavailableSubclusterException(ex)) {
           throw ex;
         }
+        return null;
       }, IOException.class);
     });