public List<MockDataNodeId> createNewDataNodes(int numNewNodes, String dcName) throws Exception {
    List<MockDataNodeId> createdNodes = new ArrayList<>();
    for (int i = 0; i < numNewNodes; ++i) {
      MockDataNodeId dataNodeId =
          createDataNode(getListOfPorts(currentPlainTextPort++, null, currentHttp2Port++), dcName,
              numMountPointsPerNode);
      dataNodes.add(dataNodeId);
      dcToDataNodes.computeIfAbsent(dcName, name -> new ArrayList<>()).add(dataNodeId);
      createdNodes.add(dataNodeId);
    }
    return createdNodes;
  }
Create a number of new nodes in given data center and add them into mock clustermap.
@param numNewNodes the number of new nodes to create
@param dcName the data center where new nodes reside
@return a list of created new nodes
ambry-test-utils/src/main/java/com/github/ambry/clustermap/MockClusterMap.java