"overwrite" is needed even for a totally empty disk, but I didn't notice it from the description:
====
overwrite:
default: "false"
type: string
description: |
If true, charm will attempt to overwrite block devices containing
previous filesystems or LVM, assuming it is not in use.
====
I specified block-device=/dev/vdb which does not have any partition table or filesystem, but charm did not setup PV on it.
[hooks/cinder_utils.py]
====
# NOTE(jamespage)
# might need todo an initial one-time scrub on install if need be
vg_found = False
new_devices = []
for device in devices:
if (not is_lvm_physical_volume(device) or
(is_lvm_physical_volume(device) and
list_lvm_volume_group(device) != volume_group)):
# Existing LVM but not part of required VG or new device
if overwrite is True:
clean_storage(device)
new_devices.append(device)
create_lvm_physical_volume(device)
====
The logic above or the description of the config can be improved, IMHO.
