Does enabling encryption on vSAN require on an-disk format change?

vSAN 6.6 shipped earlier this year. It comes with a new on-disk format to support, among other things, data at rest encryption (also known as DARE). This is version 5 of the on-disk format. I’ve been asked this question a number of times over the past week, so I thought I would quickly write a few words on whether or not enabling encryption on vSAN 6.6 requires an on-disk format change, more commonly referred to as a DFC. Now this post is not going to cover vSAN encryption in any great detail; I just want to answer this one question…

VSAN 6.2 Part 8 – Upgrading VSAN Stretched Cluster from 6.1 to 6.2

This is an exercise that we ran through in our lab environment, and we thought that the steps would be useful to share here. By way of introduction, our 4 node cluster is split into a 2+2+1 configuration, where there are 2 ESXi hosts on site A (VLAN 4), 2 ESXi hosts on site B (VLAN 3), and a third site, site C (VLAN 80), hosting the witness appliance (nested ESXi host). All sites are connected over L3. In other words, static routes are added to each of the ESXi hosts so that ESXi hosts on site A can reach…