Microsoft HPC Pack

Microsoft HPC Pack is a free HPC solution built on Microsoft Azure with Windows Server technologies and supports a wide range of HPC workloads.This page articulates the capabilities and configuration details for HPC Pack integration with Cyclecloud.

Limitations and supported versions

Microsoft HPC Pack 2016 (with Update 3) and Microsoft HPC Pack 2019 are supported in CycleCloud with below limitations:

  • The cluster must be created in an Active Directory Domain.
  • The cluster can contain only a single head node.
  • High availability on the head node is not supported yet.
  • Head node VM image customization is not supported.
  • Linux compute nodes are not supported yet.
  • The head node requires outbound internet access to download Nuget binary and Python3.
  • CLI and cloud-init configuration is not supported yet.


Active Directory Domain

Currently all HPC Pack nodes must be joined into an Active Directory Domain. If you are deploying the HPC Pack cluster in a virtual network which has a Site-to-Site VPN or ExpressRoute connection with your corporate network, typically there is already an existing Active Directory Domain. If you don't have an AD domain in your virtual network yet, you can choose to create a new AD domain by promoting the head node as domain controller.

Azure Key Vault

Microsoft HPC Pack requires a PFX certificate to secure the node communication, and it also requires AD domain user credentials to join the nodes into AD domain. While you can directly specify a PFX file, protection password, and user password in the template, we strongly recommend using Azure Key Vault for secure handling of the certificate and user password . Refer to Create an Azure Key Vault Certificate.

The cluster also requires Username and Password of an AD administrator account to join nodes to the domain as they are created. We strongly recommend to use Azure Key Vault.

Azure User Assigned Managed Identity

In order to use Azure Key Vault for the certificate and credentials , you need to create an Azure User Assigned Managed Identity and grant Get' permission for both Secret and the Certificate of the Azure Key Vault.

You can refer to this Key Vault tutorial for creating your Key Vault and a Managed Identity with Key Vault access.

We recommend using Azure Role-Based Access Control to assign Key Vault permissions to the Managed Identity.

HPC Pack node roles

There are three different node roles in HPC Pack cluster:

  • Head node: Provides the cluster management and job scheduling services. Currently, only a single head node with local databases is supported.
  • Broker node: Receives requests from an SOA client, distributes them to the service hosts on the compute nodes, and then collects responses and sends them back to the client. The broker nodes will be created in the broker node array. You must create broker nodes if you want to run an SOA workload in the cluster.
  • Compute node: Accepts and runs cluster jobs. The compute nodes will be created in the cn node array.

Create a new HPC Pack Cluster

You can click the Microsoft HPC Pack icon under Schedulers to create a new Microsoft HPC Pack cluster.

On the About page, specify a unique Cluster Name for the cluster,Since it will be used as the NetBIOS computer name of the head node, make sure it is unique in the AD domain and complies with the naming conventions.

Basic Settings

  • HPC Pack Version: You can select HPC Pack 2019 or HPC Pack 2016 (with Update 3). We recommend that you use the latest HPC Pack version, i.e. HPC Pack 2019.
  • Virtual Machines: You can select the Azure Region where you want to create the HPC Pack cluster, and the VM Type for each cluster node role. You can also specify Num. Brokers to create one or more Broker nodes if you want to run SOA workloads in the cluster.


The cluster is started without any compute nodes. You can enable Autoscale to automatically scale up/down the compute nodes depending on the cluster workloads, you can use Max Cores to specify the maximum number of compute vCPU cores of your cluster. The autoscaler runs every minute as a Windows Scheduled Task on the head node.

There are two scale-down options for compute nodes: Deallocate or Terminate. If you choose the Terminate option, the HPC Pack cluster will always remove the compute node VMs on scale-down. If you choose the Deallocate option, the HPC Pack cluster will deallocate the compute node VMs on scale-down, and maintain them for up to a configurable number of days (VM Retention Days).The deallocated compute nodes will not be removed from the HPC Pack cluster as long as they are still retained.However, they will be taken offline and shown as unreachable in the HPC Pack cluster. The Deallocate option is recommended for the HPC Pack cluster since it can significantly reduce the node preparation time on scale-up, and you only pay for the disk storage of the deallocated VMs.

Infrastructure Settings

  • Virtual Network: You can select an existing virtual network and subnet in which the HPC Pack cluster will be created.
  • Active Directory Domain: If there is already an AD domain in your virtual network, specify the full Domain Name and the OU Path in which the cluster nodes will be joined. Or select New AD Domain to create a new AD domain by promoting the head node as a domain controller.
  • Secrets and Certificate: We strongly recommend that you select Use KeyVault to use Azure Key Vault to pass the node communication certificate and user password. In MSI Identity, select Azure User Assigned Identity which you created in Prerequisites from the dropdown list, and specify the Azure Key Vault Name created in Prerequisites.
  • User Credentials: In Username, specify the domain user name. In Password Secret, specify the Azure Key Vault secret name you created in in Prerequisites to store the domain user password.
  • PFX Certificate: In Certificate Name, specify the Azure Key Vault Certificate name you created in Prerequisites.

Advanced Settings

  • Azure Settings: Select the Azure cloud Credentials from the dropdown list.
  • Cluster Software: Specify the operating system (OS) for each cluster node roles.
  • Advanced Networking: By default the DNS servers configured in the virtual network will be applied to all the HPC nodes, you can optionaly specify DNS Server if you want to use a different DNS server. You can also optionally select HN Public IP to assign a public IP address for the head node.

azhpcpack CLI

The azhpcpack.ps1 CLI is the main interface for all autoscaling behavior (the Scheduled Task calls azhpcpack.ps1 autoscale). The CLI is available in C:\cycle\hpcpack-autoscaler\bin)

The CLI can be used to diagnose issues with autoscaling or to manually control cluster scaling from inside the Head Node.

Command Description
autoscale End-to-end autoscale process, including creation, deletion and joining of nodes.
buckets Prints out autoscale bucket information, like limits etc
config Writes the effective autoscale config, after any preprocessing, to stdout
create_nodes Create a set of nodes given various constraints. A CLI version of the nodemanager interface.
default_output_columns Output what are the default output columns for an optional command.
delete_nodes Delete the node and evict from the cluster.
initconfig Creates an initial autoscale config. Writes to stdout.
limits Writes a detailed set of limits for each bucket. Defaults to json due to number of fields.
nodes Query nodes.
refresh_autocomplete Refreshes local autocomplete information for cluster specific resources and nodes.
retry_failed_nodes Retries all nodes in a failed state.
validate_constraint Validates then outputs as JSON one or more constraints.