String getRedundancyZone(InternalDistributedMember memberID) {
    return partitionedRegion.getDistributionManager().getRedundancyZone(memberID);
  }
Find the best member to put a new bucket on.

@param bucket the bucket we want to create
@param checkIPAddress true if we should only consider members that do not have the same IP
       Address as a member that already hosts the bucket
geode-core/src/main/java/org/apache/geode/internal/cache/partitioned/rebalance/model/PartitionedRegionLoadModel.java