[SOLVED] PVE Cluster - How important is it to not mix CPU types (AMD/Intel)?

[michaeljd]

Looking into setting up a cluster so I can move VMs around and have high availability. I have a mixed AMD Epyc and embedded Xeon server environment. Noticed the PVE 8.0 admin guide says this:

Online migration of virtual machines is only supported when nodes have CPUs from the same vendor. It might work otherwise, but this is never guaranteed.

My VMs are basically a bunch of Windows VMs that are used as workstations and a few Linux VMs running Pi-Hole, Plex and so on. How important is it to not mix host CPU types? Thank you.

 

[gurubert]

Online migration may work when the VMs have a CPU type of kvm64 (or qemu64) as this is a very generic virtual CPU.

You could try and set the CPU type of the VMs to the lowest common denominator of all physical CPUs. That may work.

A CPU type of host for the VM will not work.

 

[michaeljd]

Thank you for the detailed response, gurubert. It is very helpful. Currently I only have one PVE hosting all my VMs and it's an AMD EPYC system. Most of the VM CPUs are set to "host" as I remember reading you get better performance that way.

If I made all my host machines EPYC-based, would it matter what CPU type (host, kvm64, etc) the VMs were set to? Would I be able to move them between hosts without problems?

I've only been using PVE about 6 months, so still learning. Wish I'd have moved to a virtualized environment a lot sooner.

 

[gurubert]

Only if you have the same physical CPUs in all of your Proxmox nodes then you can run your VMs with CPU type "host".
Otherwise you need the lowest common denominator as CPU type for the VMs.

 

[michaeljd]

Thanks again, gurubert. Looks like I've got some more planning to do and equipment to buy before I can run a cluster.