VMware VMware vSAN is a software-defined storage tier that virtualizes the local physical storage disks available on a cluster of vSphere hosts. You specify only one datastore when creating an automated desktop pool or an automated farm, and the various components, such as virtual machine files, replicas, user data, and operating system files, are placed on the appropriate solid-state drive (SSD) disks or direct-attached hard disks (HDDs).

vSAN implements a policy-based approach to storage management. When you use vSAN, Horizon defines virtual machine storage requirements, such as capacity, performance, and availability, in the form of default storage policy profiles and automatically deploys them for virtual desktops onto vCenter Server. The policies are automatically and individually applied per disk (vSAN objects) and maintained throughout the life cycle of the virtual desktop. Storage is provisioned and automatically configured according to the assigned policies. You can modify these policies in vCenter. Horizon creates vSAN policies for instant-clone desktop pools, full-clone desktop pools, or an automated farm per Horizon cluster.

You can enable encryption for a vSAN cluster to encrypt all data-at-rest in the vSAN datastore. vSAN encryption is available with vSAN version 6.6 or later. For more information about encrypting a vSAN cluster, see the VMware vSAN documentation.

Each virtual machine maintains its policy regardless of its physical location in the cluster. If the policy becomes noncompliant because of a host, disk, or network failure, or workload changes, vSAN reconfigures the data of the affected virtual machines and load-balances to meet the policies of each virtual machine.

While supporting VMware vSphere features that require shared storage, such as HA, vMotion, and DRS, vSAN eliminates the need for an external shared storage infrastructure and simplifies storage configuration and virtual machine provisioning activities.

vSAN Workflow in Horizon

  1. When creating an automated desktop pool or an automated farm in Horizon Console, under Storage Policy Management, select Use VMware vSAN, and select the vSAN datastore to use.

    After you select Use VMware vSAN, only the vSAN datastore is displayed.

    Default storage policy profiles are created according to the clone type you choose.

  2. (Optional) Use vCenter Server to modify the parameters of the storage policy profiles, which include things like the number of failures to tolerate and the amount of SSD read cache to reserve. For specific default policies and values, see Default Storage Policy Profiles for vSAN Datastores.
  3. Use vCenter Server to monitor the vSAN cluster and the disks that participate in the datastore. For more information, see the Administering VMware vSAN document.

Requirements and Limitations

The vSAN feature has the following requirements and limitations when used in a Horizon deployment:

  • vSAN does not support VVOLs.
  • vSAN is compatible with the View Storage Accelerator feature. vSAN provides a caching layer on SSD disks, and the View Storage Accelerator feature provides a content-based cache that reduces IOPS and improves performance during boot storms.
  • Use appropriate hardware with vSAN. For specifics, see the VMware Compatibility Guide.
  • Be mindful of cluster size and the vSAN maximum limit. For more information on storage requirements and sizing limits, see the VMware Knowledge Base (KB) article https://kb.vmware.com/s/article/2150348.

For more information about vSAN requirements, see the Administering VMware vSAN document. For guidance on sizing and designing the key components of Horizon virtual desktop infrastructures for VMware vSAN, see the white paper at http://www.vmware.com/files/pdf/products/vsan/VMW-TMD-Virt-SAN-Dsn-Szing-Guid-Horizon-View.pdf.