public static String getDcName(ZNRecord znRecord) {
    return znRecord.getSimpleField(DATACENTER_STR);
  }
Get the datacenter name associated with the given instance.
@param znRecord the {@link ZNRecord} associated with the interested instance.
@return the datacenter name associated with the given instance.
ambry-clustermap/src/main/java/com/github/ambry/clustermap/ClusterMapUtils.java