diff --git a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
index ac1c8ffce9..406a3a2d8b 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
+++ b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
@@ -170,6 +170,8 @@ Trunk (unreleased changes)
     HDFS-1765. Block Replication should respect under-replication
     block priority. (Uma Maheswara Rao G via eli)
 
+    HDFS-2694. Removal of Avro broke non-PB NN services. (atm)
+
 Release 0.23.1 - UNRELEASED
 
   INCOMPATIBLE CHANGES
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NameNodeRpcServer.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NameNodeRpcServer.java
index de2a7f3472..d594766802 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NameNodeRpcServer.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NameNodeRpcServer.java
@@ -94,6 +94,7 @@
 import org.apache.hadoop.ipc.ProtocolSignature;
 import org.apache.hadoop.ipc.RPC;
 import org.apache.hadoop.ipc.Server;
+import org.apache.hadoop.ipc.WritableRpcEngine;
 import org.apache.hadoop.ipc.RpcPayloadHeader.RpcKind;
 import org.apache.hadoop.net.Node;
 import org.apache.hadoop.security.AccessControlException;
@@ -161,6 +162,8 @@ public NameNodeRpcServer(Configuration conf, NameNode nn)
 	  BlockingService NNPbService = NamenodeProtocolService
           .newReflectiveBlockingService(namenodeProtocolXlator);
     
+    WritableRpcEngine.ensureInitialized();
+    
     InetSocketAddress dnSocketAddr = nn.getServiceRpcServerAddress(conf);
     if (dnSocketAddr != null) {
       int serviceHandlerCount =