VMware's software-defined storage, which combines local devices across a cluster's ESX hosts into one shared datastore. Available as OSA or ESA, VCF can use it as principal storage.
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Terms in this definition
- General-purpose v1
The older storage account kind (
Storage), which lacks access tiers, Archive and premium file shares and retires on 13 October 2026. Converting to ZRS requires first upgrading to GPv2, a one-way change. - LSDOU
The sequence in which Group Policy is processed: the local policy first, followed by site, domain and organisational unit policies. The nearest, last-processed setting takes effect unless Enforced or Block Inheritance alters that.
- ESX
VMware's bare-metal hypervisor, installed on each host in a VCF fleet. Up to version 9.0 it was known as ESXi.
- Datastore
A named pointer in the workspace to Blob, Azure Files or ADLS Gen2 storage that keeps the connection details, so code never needs to carry storage keys itself.
- VMware Cloud Foundation
Broadcom's platform for private cloud. It unifies management of NSX, vSAN, vSphere, VCF Automation and VCF Operations as one fleet; VVF, by contrast, lacks automation and cloud management.
- principal storage
Fixed at cluster creation and impossible to switch later: vSAN (ESA or OSA), VMFS over FC, or NFS v3. Supplemental storage, by contrast, can be added afterwards.
Related terms
- Add-on licence
Before vCenter accepts this kind of entitlement, a primary one has to be in place. In 9.0 the extras are vSAN, measured per TiB, and Private AI Foundation with NVIDIA, measured per core.
- FTT
Failures to tolerate: how many disks or hosts can fail without losing a VM object, met by mirroring (RAID-1) or erasure coding (RAID-5/6). vSAN's default policy uses one.
- HCI
Hyperconverged infrastructure: x86 servers supply both processing and storage, as with vSAN pooling each ESX host's local drives into one datastore, instead of relying on external arrays or vSAN storage clusters.
- HCL
Hardware compatibility list, nowadays found in the Broadcom Compatibility Guide with the vSAN HCL database. vLCM consults it before it upgrades or remediates.
- host rebuild reserve
Spare vSAN space, optional, kept so that data lost with one failed host can be repaired. Soft, like the operations reserve: it stops new VMs or power-ons from using it up. Stretched and two-node clusters lack support for it.
- operations reserve
Space vSAN can optionally keep free for its own housekeeping. Off by default; a soft reservation that works together with the host rebuild reserve.
- primary licence
VCF or vSphere Foundation entitlement, measured per core, which vCenter needs before it will accept add-ons like vSAN TiB capacity.
- RAID-1
Mirroring in vSAN: whole duplicate copies of an object sit on separate hosts. It handles between one and three failures, at a higher capacity cost than erasure coding.