public final static String getStandbyContainerId(String activeContainerId, int replicaNumber) {
    return activeContainerId.concat(STANDBY_CONTAINER_ID_SEPARATOR).concat(String.valueOf(replicaNumber));
  }
Returns true if the containerName implies a standby container, false otherwise.
@param containerID The desired containerID
@return
samza-core/src/main/java/org/apache/samza/clustermanager/StandbyTaskUtil.java