@Override
  public int[] getMembershipPortRange() {
    return membershipPortRange;
  }
For dunit tests we do not allow use of the default multicast address/port. Please use
AvailablePort.getRandomAvailablePort(AvailablePort.JGROUPS) to obtain a free port for your
test.
geode-core/src/main/java/org/apache/geode/distributed/internal/DistributionConfigImpl.java