public static int getPrimaryPort() throws Exception {
    Region r1 = cache.getRegion(SEPARATOR + REGION_NAME);
    String poolName = r1.getAttributes().getPoolName();
    assertNotNull(poolName);
    pool = (PoolImpl) PoolManager.find(poolName);
    assertNotNull(pool);
    assertTrue(pool.getPrimaryName() != null);
    return pool.getPrimaryPort();
  }
put on non interest list ep and verify updates
geode-core/src/distributedTest/java/org/apache/geode/internal/cache/tier/sockets/InterestListEndpointDUnitTest.java