If we break it down, I'm not sure a VM will be able to boot with no volume/root disk from an image though?

I guess you could have the root VM drive all in RAM, but I don't think that Openstack understands that.

On Fri, Oct 15, 2021 at 8:55 AM Jeremy Stanley <fungi@yuggoth.org> wrote:

On 2021-10-15 11:51:49 +0100 (+0100), A Monster wrote:
> In Openstack, is it possible to create compute nodes with no hard
> drives and use PXE in order to boot the host's system
[...]

This question is outside the scope of OpenStack itself, unless
you're using another OpenStack deployment to manage the physical
servers (for example TripleO has an "undercloud" which uses Ironic
to manage the servers which then comprise the "overcloud" presented
to users). OpenStack's services start on already booted servers, so
you can in theory use any mechanism you like, including PXEboot, to
boot those physical servers. I understand OpenStack Ironic is a
great solution to this problem though, and can be set up entirely
stand-alone with its Bifrost installer.
--
Jeremy Stanley