When reimaging cloudvirt2002-dev I detected it wont autoinstall debian bullseye because the partman recipe is somehow wrong and asks for a confirmation.

By the time of this writing it uses modules/install_server/files/autoinstall/partman/custom/raid1-lvm-xfs-nova.cfg, which creates a separate LVM xfs volume for /var/lib/nova/instances.

The server is otherwise marked as 'thinvirt': hieradata/hosts/cloudvirt2002-dev.yaml:profile::openstack::base::nova::instance_dev: 'thinvirt', meaning that the separate data volume shouldn't be needed.

So there is something misconfigured somewhere.