This section describes sizing considerations to be used when planning your Horizon domains.

Sizing VI Workload Domain Capacity for Use With Horizon Domains

Sizing of hosts for a Horizon domain is complicated. Typically, this involves a user study to ensure that the workloads being used by your enterprise are well understood. For example, heavy graphical use versus simple web based applications can make a big difference to requirements.

The Digital Workspace Designer can size and estimate the hardware required to run desktop or RDSH workloads and provide server components numbers and specifications. You can then work with VMware or a certified partner to validate the input and unlock the detailed results. Refer to the Digital Workspace Tech Zone to use the online sizing tool.

Sizing a Horizon Domain

The Horizon domain is based on the Horizon Reference Architecture, which uses the Pod and Block architecture to enable you to scale as your use cases grow. In VMware Cloud Foundation, a Horizon domain is equivalent to a pod and a VI workload domain is equivalent to a block. Multiple VI workload domains can be associated with a single Horizon domain. This allows scale out to the recommended maximum of 10,000 desktops per Horizon domain.

A high level summary of scale considerations is as follows:

  • A Horizon domain (pod) can deliver a recommended maximum of 10,000 desktops
  • vCenter Server is the delimiter of a VI workload domain (block). The number of recommended VMs per vCenter Server (and therefore per block) depends on the types of VMs in use:
    • 5,000 instant clone VMs (without App Volumes)
    • 4,000 linked clone or full clone VMs (without App Volumes)
    • 2,000 VMs with App Volumes

    Hence, for a Horizon domain to support the maximum recommended 10,000 desktops with App Volumes, you would need five VI workload domains.

Other sizing considerations are as follows:

  • One Connection Server appliance per 2,000 Horizon server connections up to a maximum of seven servers
  • One Unified Access Gateway appliance per 2,000 desktop connections
  • One Composer Server per vCenter Server if traditional clones are used

It is recommended that you have two or more Connection Servers, Unified Access Gateway appliances, and App Volumes Manager instances to ensure high availability even if usage is less than the per-server maximum.

VMware Cloud Foundation also supports multiple Horizon domains (multiple pods). However, VMware Cloud Foundation does not provide automation for Cloud Pod Architecture to connect these pods. For information on manual steps, see Cloud Pod Architecture Overview in the Horizon 7 Architecture Planning document. If Cloud Pod Architecture is required to connect the pods for advanced multi-site or scale out workflows, this can be done manually.

SQL Server Sizing

A Horizon domain uses the SQL Server for storing logs and relatively static data, so there are no heavy performance requirements. For enterprise deployments, the reference architecture recommends clustered databases to be used for redundancy, especially for App Volumes and Composer Servers databases.

You can use one or more SQL Server instances for a Horizon domain. For example, you can use multiple clustered instances to separate event data from from runtime data and entitlement information.