@Override
  public boolean isDown() {
    // Cloud replica is the vcr replica that stays on public cloud, so we dont expect it to go down.
    return false;
  }
Instantiate an CloudReplica instance.
@param partitionId the {@link PartitionId} of which this is a replica.
@param dataNodeId which hosts this replica.
ambry-clustermap/src/main/java/com/github/ambry/clustermap/CloudReplica.java