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Prerequisites

Starting with Folsom, Hyper-V can be used as a compute node within OpenStack deployments.

The Hyper-V versions that are currently supported are:

  • (deprecated) Windows / Hyper-V Server 2012
  • Windows / Hyper-V Server 2012 R2
  • Windows / Hyper-V Server 2016

Newer Hyper-V versions come with an extended list of features, and can offer better overall performance. Thus, Windows / Hyper-V Server 2016 is recommended for the best experience.

Hardware requirements

Although this document does not provide a complete list of Hyper-V compatible hardware, the following items are necessary:

  • 64-bit processor with Second Level Address Translation (SLAT).
  • CPU support for VM Monitor Mode Extension (VT-c on Intel CPU's).
  • Minimum of 4 GB memory. As virtual machines share memory with the Hyper-V host, you will need to provide enough memory to handle the expected virtual workload.
  • Minimum 16-20 GB of disk space for the OS itself and updates.
  • At least one NIC, but optimally two NICs: one connected to the management network, and one connected to the guest data network. If a single NIC is used, when creating the Hyper-V vSwitch, make sure the -AllowManagementOS option is set to True, otherwise you will lose connectivity to the host.

The following items will need to be enabled in the system BIOS:

  • Virtualization Technology - may have a different label depending on motherboard manufacturer.
  • Hardware Enforced Data Execution Prevention.

To check a host's Hyper-V compatibility, open up cmd or Powershell and run:

systeminfo

The output will include the Hyper-V requirements and if the host meets them or not. If all the requirements are met, the host is Hyper-V capable.

Storage considerations

The Hyper-V compute nodes needs to have ample storage for storing the virtual machine images running on the compute nodes (for boot-from-image instances).

For Hyper-V compute nodes, the following storage options are available:

  • Local disk.
  • SMB shares. Make sure that they are persistent.
  • Cluster Shared Volumes (CSV)
    • Storage Spaces
    • Storage Spaces Direct (S2D)
    • SAN LUNs as underlying CSV storage

Compute nodes can be configured to use the same storage option. Doing so will result in faster cold / live migration operations to other compute nodes using the same storage, but there's a risk of disk overcommitment. Nova is not aware of compute nodes sharing the same storage and because of this, the Nova scheduler might pick a host it normally wouldn't.

For example, hosts A and B are configured to use a 100 GB SMB share. Both compute nodes will report as having 100 GB storage available. Nova has to spawn 2 instances requiring 80 GB storage each. Normally, Nova would be able to spawn only one instance, but both will spawn on different hosts, overcommiting the disk by 60 GB.

NTP configuration

Network time services must be configured to ensure proper operation of the OpenStack nodes. To set network time on your Windows host you must run the following commands:

net stop w32time
w32tm /config /manualpeerlist:pool.ntp.org,0x8 /syncfromflags:MANUAL
net start w32time

Keep in mind that the node will have to be time synchronized with the other nodes of your OpenStack environment, so it is important to use the same NTP server. Note that in case of an Active Directory environment, you may do this only for the AD Domain Controller.

Live migration configuration

In order for the live migration feature to work on the Hyper-V compute nodes, the following items are required:

  • A Windows domain controller with the Hyper-V compute nodes as domain members.
  • The nova-compute service must run with domain credentials. You can set the service credentials with:
sc.exe config openstack-compute obj="DOMAIN\username" password="password"

This guide contains information on how to setup and configure live migration on your Hyper-V compute nodes (authentication options, constrained delegation, migration performance options, etc), and a few troubleshooting tips.

Hyper-V Cluster configuration

compute-hyperv also offers a driver for Hyper-V Cluster nodes, which will be able to create and manage highly available virtual machines. For the Hyper-V Cluster Driver to be usable, the Hyper-V Cluster nodes will have to be joined to an Active Directory and a Microsoft Failover Cluster. The nodes in a Hyper-V Cluster must be identical.