@Test
public void testIPRange() {

  Configuration conf = new Configuration();
  conf.set(
      DefaultImpersonationProvider.getTestProvider().
          getProxySuperuserGroupConfKey(REAL_USER_NAME),
      "*");
  conf.set(
      DefaultImpersonationProvider.getTestProvider().
          getProxySuperuserIpConfKey(REAL_USER_NAME),
      PROXY_IP_RANGE);
  ProxyUsers.refreshSuperUserGroupsConfiguration(conf);
  // First try proxying a group that's allowed
  UserGroupInformation realUserUgi = UserGroupInformation
      .createRemoteUser(REAL_USER_NAME);
  UserGroupInformation proxyUserUgi = UserGroupInformation.createProxyUserForTesting(
      PROXY_USER_NAME, realUserUgi, GROUP_NAMES);
  // From good IP
  assertAuthorized(proxyUserUgi, "10.222.0.0");
  // From bad IP
  assertNotAuthorized(proxyUserUgi, "10.221.0.0");
}