Hi Sofia,

I used Backup S3 driver and the logs error from c-bak is shown below:

2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server [req-934aa717-c161-43c7-8db6-3d8ddaee046f 25cc962ecb444e0d8e28c843782958f5 ca53347fad024242bc91e7a11b87db16 - - -] Exception during message handling: cinder.exception.InvalidBackup: Invalid backup: Volume size increased since the last backup. Do a full backup.
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server Traceback (most recent call last):
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server   File "/var/lib/kolla/venv/lib/python3.8/site-packages/oslo_messaging/rpc/server.py", line 165, in _process_incoming
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server     res = self.dispatcher.dispatch(message)
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server   File "/var/lib/kolla/venv/lib/python3.8/site-packages/oslo_messaging/rpc/dispatcher.py", line 309, in dispatch
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server     return self._do_dispatch(endpoint, method, ctxt, args)
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server   File "/var/lib/kolla/venv/lib/python3.8/site-packages/oslo_messaging/rpc/dispatcher.py", line 229, in _do_dispatch
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server     result = func(ctxt, **new_args)
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server   File "/var/lib/kolla/venv/lib/python3.8/site-packages/cinder/utils.py", line 890, in wrapper
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server     return func(self, *args, **kwargs)
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server   File "/var/lib/kolla/venv/lib/python3.8/site-packages/cinder/backup/manager.py", line 410, in create_backup
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server     volume_utils.update_backup_error(backup, str(err))
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server   File "/var/lib/kolla/venv/lib/python3.8/site-packages/oslo_utils/excutils.py", line 227, in __exit__
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server     self.force_reraise()
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server   File "/var/lib/kolla/venv/lib/python3.8/site-packages/oslo_utils/excutils.py", line 200, in force_reraise
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server     raise self.value
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server   File "/var/lib/kolla/venv/lib/python3.8/site-packages/cinder/backup/manager.py", line 399, in create_backup
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server     updates = self._run_backup(context, backup, volume)
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server   File "/var/lib/kolla/venv/lib/python3.8/site-packages/cinder/backup/manager.py", line 482, in _run_backup
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server     updates = backup_service.backup(
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server   File "/var/lib/kolla/venv/lib/python3.8/site-packages/cinder/backup/chunkeddriver.py", line 587, in backup
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server     raise exception.InvalidBackup(reason=err)
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server cinder.exception.InvalidBackup: Invalid backup: Volume size increased since the last backup. Do a full backup.
2022-10-13 19:48:00.605 22 ERROR oslo_messaging.rpc.server