Infinidat Cinder driver fails to backup attached volume

[Alexander Deiter]

For some unknown reason, the Infinidat Cinder driver does not allow to backup the attached volume. This makes it impossible to backup for most use cases.

Steps to reproduce:
* Install an OpenStack environment: Queens or newer version
* Configure Infinidat iSCSI or FC backend
* Create a volume
* Boot a VM instance
* Attach the volume to the VM instance
* Try to backup the attached volume

Expected results:
Success

Actual results:
Error: INFINIDAT Cinder driver does not support clone of an attached volume. To get this done, create a snapshot from the attached volume and then create a volume from the snapshot.

Traceback (most recent call last):
  File "/usr/local/lib/python3.8/dist-packages/oslo_messaging/rpc/server.py", line 165, in _pro
cess_incoming
    res = self.dispatcher.dispatch(message)
  File "/usr/local/lib/python3.8/dist-packages/oslo_messaging/rpc/dispatcher.py", line 309, in
dispatch
    return self._do_dispatch(endpoint, method, ctxt, args)
  File "/usr/local/lib/python3.8/dist-packages/oslo_messaging/rpc/dispatcher.py", line 229, in
_do_dispatch
    result = func(ctxt, **new_args)
  File "/opt/stack/cinder/cinder/volume/manager.py", line 4745, in get_backup_device
    self.driver.get_backup_device(ctxt, backup))
  File "/opt/stack/cinder/cinder/volume/driver.py", line 1194, in get_backup_device
    backup_device = self._get_backup_volume_temp_volume(
  File "/opt/stack/cinder/cinder/volume/driver.py", line 1236, in _get_backup_volume_temp_volume
    temp_vol_ref = self._create_temp_cloned_volume(
  File "/opt/stack/cinder/cinder/volume/driver.py", line 1348, in _create_temp_cloned_volume
    temp_vol_ref.destroy()
  File "/usr/local/lib/python3.8/dist-packages/oslo_utils/excutils.py", line 227, in __exit__
    self.force_reraise()
  File "/usr/local/lib/python3.8/dist-packages/oslo_utils/excutils.py", line 200, in force_reraise
    raise self.value
  File "/opt/stack/cinder/cinder/volume/driver.py", line 1343, in _create_temp_cloned_volume
    model_update = self.create_cloned_volume(temp_vol_ref, volume)
  File "/opt/stack/cinder/cinder/volume/drivers/infinidat.py", line 96, in wrapper
    return func(*args, **kwargs)
  File "/opt/stack/cinder/cinder/volume/drivers/infinidat.py", line 727, in create_cloned_volume
    self._asssert_volume_not_mapped(src_vref)
  File "/opt/stack/cinder/cinder/volume/drivers/infinidat.py", line 713, in _asssert_volume_not_mapped
    raise exception.VolumeBackendAPIException(data=msg)
cinder.exception.VolumeBackendAPIException: Bad or unexpected response from the storage volume backend API: INFINIDAT Cinder driver does not support clone of an attached volume. To get this done, create a snapshot from the attached volume and then create a volume from the snapshot.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/cinder/+/851640

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/cinder/+/851640
Committed: https://opendev.org/openstack/cinder/commit/907550015e0480fac3e69c5fc73f11f825723bf4
Submitter: "Zuul (22348)"
Branch: master

commit 907550015e0480fac3e69c5fc73f11f825723bf4
Author: Alexander Deiter <email address hidden>
Date: Mon May 23 21:36:35 2022 +0400

    Fix Infinidat driver to backup attached volume

    For some historical reason, the Infinidat Cinder driver does not
    allow to backup an attached volume. This makes it impossible to
    create a backup for most use cases. As a possible solution we can
    create and use snapshots as a backup source.

    This patch implements attach/detach for snapshots and the ability
    to use snapshots to perform non-disruptive backups.

    Added functions:
    * initialize_connection_snapshot()
    * terminate_connection_snapshot()
    * create_export_snapshot()
    * remove_export_snapshot()
    * backup_use_temp_snapshot()

    And changed functions:
    * create_volume_from_snapshot()
    * create_cloned_volume()

    remove the duplicated code and use the temporary snapshot
    as the source for creating the cloned volume.

    Closes-bug: #1983287
    Change-Id: I0e1534c6015eaa8baef48b7878324625a4cc9f1a
    Signed-off-by: Alexander Deiter <email address hidden>

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/cinder 22.0.0.0rc1 release candidate.