Starting in Train there is a new config option for Pure Storage arrays called pure_iscsi_cidr. It is ipv4 only and if you have a Pure Storage FlashArray configured with ipv6 iscsi it will fail while building an instance on a cinder volume with this message
VolumeBackendAPIException: Bad or unexpected response from the storage volume backend API: Driver initialize connection failed (error: Expected 4 octets in u'[2620').
The problem lies in volume/drives/pure.py where it's hardcoded to expect an ipv4 address
# Check to ensure all returned portal IP addresses
# are in iSCSI target CIDR
if not isinstance(self.configuration.pure_iscsi_cidr, six.text_type):
cidr = self.configuration.pure_iscsi_cidr.decode('utf8')
else:
cidr = self.configuration.pure_iscsi_cidr
check_cidr = ipaddress.IPv4Network(cidr)
for target_portal in target_portals:
if not isinstance(target_portal.split(":")[0], six.text_type):
portal = (target_portal.split(":")[0]).decode('utf8')
else:
portal = target_portal.split(":")[0]
check_ip = ipaddress.IPv4Address(portal)
if check_ip in check_cidr:
valid_portals.append(target_portal)
LOG.info("iSCSI target portals that match CIDR range: '%s'",
valid_portals)
Previous to Train this worked fine with ipv6 iscsi. It needs to be patched from master all the way back to the Train release.
This issue was fixed in the openstack/cinder 19.0.0.0b1 development milestone.