@Override
  public void healthChanged(GemFireVM member, GemFireHealth.Health status) {
    if (status == GOOD_HEALTH) {
      okayHealth.remove(member);
      poorHealth.remove(member);

    } else if (status == OKAY_HEALTH) {
      okayHealth.add(member);
      poorHealth.remove(member);

    } else if (status == POOR_HEALTH) {
      okayHealth.remove(member);
      poorHealth.add(member);

    } else {
      Assert.assertTrue(false, "Unknown health code: " + status);
    }

    reevaluateHealth();
  }
Re-evaluates the overall health of GemFire
geode-core/src/main/java/org/apache/geode/admin/internal/GemFireHealthImpl.java