code: private String getInfoServer() throws IOException {
      URI fsName = FileSystem.getDefaultUri(conf);
      if (!"hdfs".equals(fsName.getScheme())) {
        throw new IOException("This is not a DFS");
      }
      return NetUtils.getServerAddress(conf, "dfs.info.bindAddress", 
                                       "dfs.info.port", "dfs.http.address");
    }
docs: Returns the Jetty server that the Namenode is listening on.