@Override
  public MetricRegistry getMetricRegistry() {
    return staticClusterManager.getMetricRegistry();
  }
The list of {@link DataNodeId}s present in the underlying {@link HelixClusterManager}
@return the list of {@link DataNodeId}s present in the underlying {@link HelixClusterManager}
ambry-clustermap/src/main/java/com/github/ambry/clustermap/RecoveryTestClusterManager.java