Setting UUID for KVM VM?

[victorhooi]

Hi,

What is the current best practice in Proxmox for setting the SMBIOS UUID for a KVM virtual machine?

(This older post mentions a `/etc/qemu-server/VMID.conf`, but that's no longer valid, I assume).

I see from the qm.conf for my VMs that there's a smbios1 uuid field.

1. What's the best way to edit this field? It doesn't to be exposed in the web GUI - is there a programmatic way of doing it.

2. When you clone a KVM VM - does it generate a random new UUID? (I believe it does, right, just from checking my machine, but wanted to be sure).

3. Are there any issues from having multiple machines running on the same node with the same UUID?

Regards,
Victor

 

[victorhooi]

4. If you clone a KVM VM from a template - does it always randomly generate a new UUID? Is there any way to have it re-use a fixed UUID?

 

[dcsapak]

1. What's the best way to edit this field? It doesn't to be exposed in the web GUI - is there a programmatic way of doing it.

sure its exposed vm -> options -> smbios
but you can set it via 'qm set <ID> -smbio1 uuid=<uuid>'

2. When you clone a KVM VM - does it generate a random new UUID? (I believe it does, right, just from checking my machine, but wanted to be sure).

yes

3. Are there any issues from having multiple machines running on the same node with the same UUID?

from our stack, no

4. If you clone a KVM VM from a template - does it always randomly generate a new UUID? Is there any way to have it re-use a fixed UUID?

no, clone always generates a new one, but you can set it back to the fixed one via gui/cli/api