After you complete your ESXi update, upgrade the vSAN on-disk format to access the complete feature set of vSAN.
Each vSAN release supports the on-disk format of prior releases. All hosts in the cluster must have the same on-disk format version. Because some features are tied to the on-disk format version, it's best to upgrade the vSAN on-disk format to the highest version supported by the ESXi version. For more information, refer to https://kb.vmware.com/s/article/2148493.
vSAN on-disk format version 3 and higher require only a metadata upgrade that takes a few minutes. No disk evacuation or reconfiguration is performed during the on-disk format upgrade.
Before you upgrade the vSAN on-disk format, run the Pre-Check Upgrade to ensure a smooth upgrade. The pre-check identifies potential issues that might prevent a successful upgrade, such as failed disks or unhealthy objects.
