[Evms-devel] A new disk is created when snapshot rollback is done

[GNVS S. <ssu...@no...>]

Hi,

I am facing a problem where a whole new volume and a new associated
disk is being created when I use snapshot rollback. One thing to note is
I am creating and deleting a volume and then using its associated region
for snapshot. 

I am able to reproduce this on 5 machines. Here are the steps. Steps
like 16 are not needed but I am writing as I followed the steps.

Steps:

1. Use evmsgui

2. From the Freespace region from an LVM2 container create the
following two regions:
vm_region1 : 500 MB
vm_snap_region1: 300MB

3. Create volumes vm_vol1 on vm_region1 and vm_snap_vol1 on
vm_snap_region1.

4. Delete vm_snap_vol1 and create ReiserFs file system on vm_vol1

5. Save changes and come out of evmsgui.

6. mkdir /mnt/vm_vol1

7. mount /dev/evms/vm_vol1 /mnt/vm_vol1

8. echo "111111111111111" >  /mnt/vm_vol1/a.txt

9. evmsgui

10. Actions > Feature Object > *select Snapshot Feature*  Next >
*select vm_snap_region1* Next > *select /dev/evms/vm_vol1, snap obj
name=snap_obj_vm_snap_vol1* Create. 

11. Create vm_snap_vol1 volume on snap_obj_vm_snap_vol1. 

12. Save changes and come out of evmsgui.

13. mount /dev/evms/vm_snap_vol1 /mnt/vm_snap_vol1

14. echo "222222222222" >> /mnt/vm_snap_vol1/a.txt

15. cp -r /usr/include/* /mnt/vm_vol1

16. evmsgui

17. See percentage filled. Come out of evmsgui.

18. umount  /mnt/vm_vol1

19. umount /mnt/vm_snap_vol1

20. evmsgui

21. Actions > Other > Storage Object Tasks ... > *select
snap_obj_vm_snap_vol1* Next > *select Roll Back* Next > Rollback.
Complete the steps for rollback.

22. Save changes and come out of evmsgui.

23. mount /dev/evms/vm_vol1 /mnt/vm_vol1

24. evmsgui

25. Delete vm_snap_vol1

26. Delete snap_obj_vm_snap_vol1

27. Delete vm_snap_region1

28. Save changes and come out of evmsgui.

29. evmsgui

30. Now you can see a volume /dev/evms/dm-8 (or dm-9 like) and a new
disk dm-8 associated with it.


Let me know if I am wrong anywhere.

Thanks
Sudhakar