Disadvantages to enabling nesting?

[Terminatrix]

I know that some big hosting providers like Contabo which uses Proxmox disabled nesting inside their normal VPS packages.

Why would you say they do this? What are the disadvantages if for example I am using 6 cores/1 socket.

 

[Felix.]

Why would you say they do this?

https://pve.proxmox.com/wiki/Nested_Virtualization
For example: VMs with nested virtualization cannot be live-migrated.
That alone is a good reason for a hoster to disable this feature, because it prevents the VM from being HA-migrated in case the host dies.

 

[Terminatrix]

https://pve.proxmox.com/wiki/Nested_Virtualization
For example: VMs with nested virtualization cannot be live-migrated.
That alone is a good reason for a hoster to disable this feature, because it prevents the VM from being HA-migrated in case the host dies.

I have done that though. There was no errors shown, both had the same CPU. I think it does work if you have host as CPU type?

 

[Felix.]

I think it does work if you have host as CPU type?

Wait. You had nesting enabled on 2 physical hosts and installed a VM with nesting enabled in settings and live migration works?

 

[Terminatrix]

Wait. You had nesting enabled on 2 physical hosts and installed a VM with nesting enabled in settings and live migration works?

Yes https://forum.proxmox.com/threads/proxmox-6-3-qemu-5-1-nested-live-migration-on-intel-cpu.79698/

 

[Felix.]

Yes https://forum.proxmox.com/threads/proxmox-6-3-qemu-5-1-nested-live-migration-on-intel-cpu.79698/

Freaking amazing! Love it!
I'll test that in some spare time

 

[Terminatrix]

Yes it's nice now I need to just work on getting cloud-init to work live migration haha

Can you think of any other reasons? I can only think that maybe they don't want users to sell virtual machines as those users would use more total resources.

 

[Felix.]

Do they passthrough a cpu of type qemu/kvm64 oder host?
If they switch their server hardware or if they use different host servers and try to migrate vms, things may break on customer side.
When customers virtualize to their customers, this problem gets exponentially worse.

Nesting is not enabled by default, thats probably why they simply dont use it.

Shared resources on VPS may be a concern, but honestly, if they want to mess with them, customers could run a benchmark 24/7 and call it a day.

 

[Terminatrix]

Do they passthrough a cpu of type qemu/kvm64 oder host?
If they switch their server hardware or if they use different host servers and try to migrate vms, things may break on customer side.
When customers virtualize to their customers, this problem gets exponentially worse.

Nesting is not enabled by default, thats probably why they simply dont use it.

Shared resources on VPS may be a concern, but honestly, if they want to mess with them, customers could run a benchmark 24/7 and call it a day.

They enable host flag and they use the same hardware too as far as I can see (different countries use different hardware but each region seems to be the same).