public static Integer getSslPortStr(InstanceConfig instanceConfig) {
    return getSslPortStr(instanceConfig.getRecord());
  }
Get the ssl port associated with the given instance (if any).
@param instanceConfig the {@link InstanceConfig} associated with the interested instance.
@return the ssl port associated with the given instance.
ambry-clustermap/src/main/java/com/github/ambry/clustermap/ClusterMapUtils.java