@ConfigAttributeChecker(name = MEMBERSHIP_PORT_RANGE)
  protected int[] checkMembershipPortRange(int[] value) {
    minMaxCheck(MEMBERSHIP_PORT_RANGE, value[0], 1024, value[1]);
    minMaxCheck(MEMBERSHIP_PORT_RANGE, value[1], value[0], 65535);

    // Minimum 3 ports are required to start a Gemfire data node,
    // One for each, UDP, FD_SOCk protocols and Cache Server.
    if (value[1] - value[0] < 2) {
      throw new IllegalArgumentException(
          String.format(
              "Could not set \"%s\" to \"%s\" because its value can not be less than \"%s\".",
              MEMBERSHIP_PORT_RANGE, value[0] + "-" + value[1],
              3));
    }
    return value;
  }
check a new mcast flow-control setting
geode-core/src/main/java/org/apache/geode/distributed/internal/AbstractDistributionConfig.java