Instant-clone virtual machines can be stored on local datastores, which are internal spare disks on ESXi hosts. Local storage offers advantages such as inexpensive hardware, fast virtual-machine provisioning, high performance power operations, and simple management. However, using local storage limits the vSphere infrastructure configuration options that are available to you. Using local storage is beneficial in certain Horizon environments but not appropriate in others.
Using local datastores is most likely to work well if the Horizon desktops in your environment are non-persistent. For example, you might use local datastores if you deploy kiosks or classroom and training stations.
Consider using local datastores if your virtual machines have floating assignments, are not dedicated to individual end users, do not require persistent disks for user data, and can be deleted or refreshed at regular intervals such as on user logoff. This approach lets you control the disk usage on each local datastore without having to move or load-balance the virtual machines across datastores.
However, you must consider the restrictions that using local datastores imposes on your Horizon desktop or farm deployment:
- You cannot use VMotion.
- You cannot use VMware vSphere High Availability.
- You cannot use the vSphere Distributed Resource Scheduler (DRS).
- If you are deploying instant clones on a single ESXi host with a local datastore, you must configure a cluster containing that single ESXi host. If you have a cluster of two or more ESXi hosts with local datastores, select the local datastore from each of the hosts in the cluster. Otherwise, instant clone creation fails..
- Local spinning-disk drives and a storage array might have similar capacity, but local spinning-disk drives do not have the same throughput as a storage array. Throughput increases as the number of spindles grows. If you select direct attached solid-state disks (SSDs), performance is likely to exceed that of many storage arrays. Local datastore support for instant clones is available for both virtual desktops and published desktops