On 2022-06 -07, at 13:25, Sean Mooney <smooney@redhat.com> wrote:

no there is noting else you need to configure but this option is not what you think it is.
the images_type option contols what storage will be used for all non cinder storage.
i.e. vms that are booted with out usign a boot volume.

by default i belive we woudl use qcow or raw files on disk
with images_type=lvm we will instead create a lvm volume for the root disk but only if you do not use the boot form volume workflow.

there is no way curretnly to prevent usign boot form volume on a specific host and force only local storage directly via config.

you can do this indirectly but with sideffect.

effectivly if you have a set of hosts that cant or should not have acess to cinder you can create a spereate avaiablity zone.
you would then set [cinder]/cross_az_attch=false. e.g. create local-only az and if the cinder backend is configured to be in a differnt az then
the cross_az_attach config will prevent the vm form booting in the local-only az.
https://docs.openstack.org/nova/latest/configuration/config.html#cinder.cross_az_attach


so your current config will make any non boot from volume nova instance use lvm storage to provision the vm root/swap/epmeral disks
but will not prevent end users requesting cinder data voluems or boot volumes via the cli/api. if the opt in to cinder stoage that
is what they will recive but if they use teh default storage provided by the flaovr then it will be local.