hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/webapp/RedirectionErrorPage.java

/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements.  See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership.  The ASF licenses this file
* to you 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
*
*     http://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.
*/

package org.apache.hadoop.yarn.server.resourcemanager.webapp;

import org.apache.hadoop.yarn.webapp.SubView;
import org.apache.hadoop.yarn.webapp.YarnWebParams;

/**
 * This class is used to display a message that the proxy request failed
 * because of a redirection issue.
 */
public class RedirectionErrorPage extends RmView {
  @Override protected void preHead(Page.HTML<_> html) {
    String aid = $(YarnWebParams.APPLICATION_ID);

    commonPreHead(html);
    set(YarnWebParams.ERROR_MESSAGE,
        "The application master for " + aid + " redirected the "
        + "resource manager's web proxy's request back to the web proxy, "
        + "which means your request to view the application master's web UI "
        + "cannot be fulfilled. The typical cause for this error is a "
        + "network misconfiguration that causes the resource manager's web "
        + "proxy host to resolve to an unexpected IP address on the "
        + "application master host. Please contact your cluster "
        + "administrator to resolve the issue.");
  }

  @Override protected Class<? extends SubView> content() {
    return ErrorBlock.class;
  }
}