public static String getSecondaryNameServiceId(Configuration conf) {
    return getNameServiceId(conf, DFS_NAMENODE_SECONDARY_HTTP_ADDRESS_KEY);
  }
@Test
  public void getSecondaryNameServiceId() {
    Configuration conf = setupAddress(DFS_NAMENODE_SECONDARY_HTTP_ADDRESS_KEY);
    assertEquals("nn1", DFSUtil.getSecondaryNameServiceId(conf));
  }