Because vSAN is a kernel-based solution, upgrading vSAN requires upgrading the vSphere hypervisor. The VMware vSphere Update Manager (VUM) can be used to automate the upgrade process of hosts in a vSAN cluster. When upgrading, you can choose between two evacuation modes: Ensure Accessibility or Full Data Migration.
VMware Update Manager (VUM) builds recommendations for vSAN. Update Manager can scan the vSAN cluster and recommend host baselines that include updates, patches, and extensions. It manages recommended baselines, validates the support status from vSAN HCL, and downloads the correct ESXi ISO images from VMware.
vSAN 6.7 U1 performs a simulation of data evacuation to determine if the operation will succeed or fail before it starts. If the evacuation will fail, vSAN halts the operation before any resynchronization activity begins. In addition, the vSphere Client enables end users to modify the component repair delay timer.