I just downloaded a patch [1] file and applied to glance_store using patch -p1 command and I have verified it properly patch rbd.py driver file as per original patch. Next question is do I need to re-upload the snapshot in order to test this patch or will it work with the existing snapshot. 

[1] https://review.opendev.org/c/openstack/glance_store/+/896447



On Thu, Jan 25, 2024 at 12:38 AM Abhishek Kekane <akekane@redhat.com> wrote:

On Thu, Jan 25, 2024 at 2:05 AM Satish Patel <satish.txt@gmail.com> wrote:
Hi Abhishek/Eugen, 

I found this solution and it works with patches or anything. Just flatten the image as Eugen mentioned without doing any hassle. Just find children and flatten it and delete the image from glance. I wish glance api had a flag to pass --flatten flag to make it work. 

@Abhishek Kekane I would like to follow up with you about your patch. Why is it not working for me? 

I am not sure where and how you applied the patch and what steps you taken after applying the patch.

- Abhishek

# rbd children images/3708f961-fb74-49f1-ab9b-40cf7954abed
volumes/volume-f2b2aec2-cc57-49e5-aca1-54b5a7ee9f3a

# rbd du volumes/volume-f2b2aec2-cc57-49e5-aca1-54b5a7ee9f3a
NAME                                         PROVISIONED  USED
volume-f2b2aec2-cc57-49e5-aca1-54b5a7ee9f3a       40 GiB  8.1 GiB   <-- 8.1 GB

# rbd flatten volumes/volume-f2b2aec2-cc57-49e5-aca1-54b5a7ee9f3a
Image flatten: 100% complete...done.

# rbd du volumes/volume-f2b2aec2-cc57-49e5-aca1-54b5a7ee9f3a
NAME                                         PROVISIONED  USED
volume-f2b2aec2-cc57-49e5-aca1-54b5a7ee9f3a       40 GiB  8.5 GiB <-- 8.5 GB



# openstack image delete 3708f961-fb74-49f1-ab9b-40cf7954abed
#




On Wed, Jan 24, 2024 at 2:39 PM Satish Patel <satish.txt@gmail.com> wrote:
Hi Abhishek,

Do you think this error means I have a protected snapshot? 

# rbd snap ls images/3708f961-fb74-49f1-ab9b-40cf7954abed
SNAPID  NAME  SIZE    PROTECTED  TIMESTAMP
    55  snap  40 GiB  yes        Wed Jan 17 13:41:35 2024

On Wed, Jan 24, 2024 at 2:05 PM Satish Patel <satish.txt@gmail.com> wrote:
I did apply this patch by patch command (manually)  - https://review.opendev.org/c/openstack/glance_store/+/896447 

Still getting errors. Do I need to do anything else like recreate instance or snapshot etc. 

2024-01-24 19:03:53.165 47 WARNING glance_store._drivers.rbd [None req-c4d10e8a-1bc3-496c-8df1-6156582d760f 93e2d918bc7a4d92a93df927743d00ff 08cae850a5bb47d998da180a7f0e2660 - - default default] Snap Operating Exception [errno 16] RBD image is busy (error unprotecting snapshot b'3708f961-fb74-49f1-ab9b-40cf7954abed'@b'snap') Snapshot is in use.: rbd.ImageBusy: [errno 16] RBD image is busy (error unprotecting snapshot b'3708f961-fb74-49f1-ab9b-40cf7954abed'@b'snap')
2024-01-24 19:03:53.171 47 WARNING glance.api.v2.images [None req-c4d10e8a-1bc3-496c-8df1-6156582d760f 93e2d918bc7a4d92a93df927743d00ff 08cae850a5bb47d998da180a7f0e2660 - - default default] Image 3708f961-fb74-49f1-ab9b-40cf7954abed could not be deleted because it is in use: The image cannot be deleted because it is in use through the backend store outside of Glance.: glance_store.exceptions.InUseByStore: The image cannot be deleted because it is in use through the backend store outside of Glance.

On Wed, Jan 24, 2024 at 1:54 PM Abhishek Kekane <akekane@redhat.com> wrote:
Hi Satish,

This needs to be applied on glance_store and not glance.

Thanks & Best Regards,

Abhishek Kekane


On Thu, Jan 25, 2024 at 12:18 AM Satish Patel <satish.txt@gmail.com> wrote:
Hi Abhishek,

I found a patch here - https://review.opendev.org/c/openstack/glance_store/+/896447 Can I just simplay apply this patch on existing glance and see if it works or not? 

On Wed, Jan 24, 2024 at 12:07 PM Abhishek Kekane <akekane@redhat.com> wrote:
Hi Satish,

Which version of openstack are you using?
In bobcat (glance_store version 4.6.0) we have added a feature [1] RBD Trash to cover the issue you described.

Pre bobcat (glance_store version < 4.6.0), deletion of snapshot will fail with the issue you described.



Thanks & Best Regards,

Abhishek Kekane



On Wed, Jan 24, 2024 at 10:26 PM Satish Patel <satish.txt@gmail.com> wrote:
Folks,

I have two openstack clouds and both have their own Ceph backend storage.I am trying to migrate instances from openstack A to openstack B. 

1. Take a snapshot from A
2.  Export snapshot and import to B 
3. Create instance on B 
4. Delete snapshot - (I am getting error because its in-use) 

Because it has a parent reference to that volume. How do I remove the reference so it will let me delete a snapshot. Reason I am asking is because I have so many VMs to migrate and don't want glance to have 100s of entities in those snapshots. 

What is the alternative here? I can try qcow2 if that is the final solution to make it clean. 
# rbd -p volumes info volume-f2b2aec2-cc57-49e5-aca1-54b5a7ee9f3a
rbd image 'volume-f2b2aec2-cc57-49e5-aca1-54b5a7ee9f3a':
	size 40 GiB in 5120 objects
	order 23 (8 MiB objects)
	snapshot_count: 0
	id: 5473c827864fed
	block_name_prefix: rbd_data.5473c827864fed
	format: 2
	features: layering, exclusive-lock, object-map, fast-diff, deep-flatten
	op_features:
	flags:
	create_timestamp: Fri Jan 19 19:03:25 2024
	access_timestamp: Wed Jan 24 15:51:04 2024
	modify_timestamp: Wed Jan 24 15:52:40 2024
	parent: images/3708f961-fb74-49f1-ab9b-40cf7954abed@snap
	overlap: 40 GiB