HDFS-14516. RBF: Create hdfs-rbf-site.xml for RBF specific properties. Contributed by Takanobu Asanuma.

hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/conf/hdfs-rbf-site.xml

@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+  https://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+-->
+
+<!-- Put site-specific property overrides in this file. -->
+
+<configuration>
+
+</configuration>

hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RBFConfigKeys.java

@@ -19,6 +19,7 @@
 package org.apache.hadoop.hdfs.server.federation.router;
 
 import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.CommonConfigurationKeysPublic;
 import org.apache.hadoop.hdfs.server.federation.metrics.FederationRPCPerformanceMonitor;
 import org.apache.hadoop.hdfs.server.federation.resolver.ActiveNamenodeResolver;
@@ -39,6 +40,12 @@ import java.util.concurrent.TimeUnit;
 @InterfaceAudience.Private
 public class RBFConfigKeys extends CommonConfigurationKeysPublic {
 
+  public static final String HDFS_RBF_SITE_XML = "hdfs-rbf-site.xml";
+
+  static {
+    Configuration.addDefaultResource(HDFS_RBF_SITE_XML);
+  }
+
   // HDFS Router-based federation
   public static final String FEDERATION_ROUTER_PREFIX =
       "dfs.federation.router.";

hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/resources/hdfs-rbf-default.xml

@@ -19,8 +19,8 @@
 -->
 
 <!-- Do not modify this file directly.  Instead, copy entries that you -->
-<!-- wish to modify from this file into hdfs-site.xml and change them -->
-<!-- there.  If hdfs-site.xml does not already exist, create it.      -->
+<!-- wish to modify from this file into hdfs-rbf-site.xml and change them -->
+<!-- there.  If hdfs-rbf-site.xml does not already exist, create it.      -->
 
 <configuration>
   <property>

hadoop-hdfs-project/hadoop-hdfs-rbf/src/site/markdown/HDFSRouterFederation.md

@@ -349,7 +349,7 @@ This federated namespace can also be set as the default one at **core-site.xml**
 Router configuration
 --------------------
 
-One can add the configurations for Router-based federation to **hdfs-site.xml**.
+One can add the configurations for Router-based federation to **hdfs-rbf-site.xml**.
 The main options are documented in [hdfs-rbf-default.xml](../hadoop-hdfs-rbf/hdfs-rbf-default.xml).
 The configuration values are described in this section.