On Tue, 2022-12-27 at 17:40 +0200, Zakhar Kirpichenko wrote:
> Hi! 
>
> I'd like to have the following configuration added to every guest on a
> specific host managed by Nova and libvirt/kvm: 
>
>     <sound model='bla'>
>       <address type='pci' domain='0x0000' bus='0x00' slot='0x1b'
> function='0x0'/>
>     </sound>
>
> When I add the device manually to instance xml, it works as intended but the
> instance configuration gets overwritten on instance stop/start or hard reboot
> via Nova.

Modifying libvirt's XML behind nova's back is a big no-no. You break the
contract between the two. If you wanted audio support, you'd need to add this
support to nova itself. This would require a spec, quite a bit of coding, and
would not be backported. tbh, it's also hard to see this being prioritized since
audio support for cloud-based VMs is a rather unusual request. If you wanted to
persue this approach though, feel free to reach out on IRC (#openstack-nova on
OFTC) and we can guide you.

Stephen

>
> What is the currently supported / proper way to add a virtual sound device
> without having to modify libvirt or Nova code? I would appreciate any advice. 
>
> Best regards, 
> Zakhar