Hi Philip, I am allowing Harvester/Longhorn to use the entire NVMe (all four of them) in each node, as it wants to. There is no RAID in between, did I imply this in my original post somehow? I apologize if I did. It seems when you do allow Harvester/Longhorn to manage the NVMe’s directly, you are limited to the smallest NVMe disk size and the formula you have nicely documented as the worst case for file size. The number of changes and modifications on the VM disk itself will determine the actual “worst case” requirement, which can be difficult to calculate if the Administrator isn’t tracking such things prior to migration of VMs into Harvester/Longhorn.
[edit] - Oh! I see your confusion. You are misunderstanding my reply. I am comparing our production SLE 15 KVM single server with RAID 10 and XFS for the local VM disk images to 1.5 Harvester/Longhorn four node cluster on a dedicated 25gbe network. Same exact virtual machines on a new generation, four node Harvester as configured. We haven’t experienced any disk corruption on SLE 15 KVM alone in a decade. It happened on day three in testing on Harvester.