[ovirt-users] Can't remove snapshot

Tue Feb 16 13:50:04 UTC 2016

Hi,

I'm trying to determine the correct "bad_img" uuid in my case.

The VM has two snapshots:

* The "Active VM" snapshot which has a disk that has an actual size
that's 5GB larger than the virtual size. It has a creation date that
matches the timestamp at which I created the second snapshot. The "disk
snapshot id" for this snapshot ends with dc39.

* A "before jessie upgrade" snapshot that has status "illegal". It has
an actual size that's 2GB larger than the virtual size. The creation
date matches the date the VM was initialy created. The disk snapshot id
ends with 6249.

>From the above I conclude that the disk with id that ends with 6249 is
the "bad" img I need to specify.

However, I grepped the output from 'lvs' on the SPM host of the cluster
and both disk id's are returned:

[root at amazone ~]# lvs | egrep 'cd39|6249'
  24d78600-22f4-44f7-987b-fbd866736249
a7ba2db3-517c-408a-8b27-ea45989d6416 -wi-ao----   34.00g

  81458622-aa54-4f2f-b6d8-75e7db36cd39
a7ba2db3-517c-408a-8b27-ea45989d6416 -wi-------    5.00g

I expected the "bad" img would no longer be found?

The SQL script only cleans up the database and not the logical volumes.
Would running the script not keep a stale LV around?

Also, from the lvs output it seems the "bad" disk is bigger than the
"good" one.

Is it possible the snapshot still needs to be merged?? If so, how can I
initiate that?

Regards,

Rik

On 02/16/2016 02:02 PM, Rik Theys wrote:
> Hi Greg,
> 
>>
>> 2016-02-09 21:30 GMT-03:00 Greg Padgett <gpadgett at redhat.com>:
>>> On 02/09/2016 06:08 AM, Michal Skrivanek wrote:
>>>>
>>>>
>>>>> On 03 Feb 2016, at 10:37, Rik Theys <Rik.Theys at esat.kuleuven.be> wrote:
> 
>>>>>> I can see the snapshot in the "Disk snapshot" tab of the storage. It has
>>>>>> a status of "illegal". Is it OK to (try to) remove this snapshot? Will
>>>>>> this impact the running VM and/or disk image?
>>>>
>>>>
>>>> No, it’s not ok to remove it while live merge(apparently) is still ongoing
>>>> I guess that’s a live merge bug?
>>>
>>>
>>> Indeed, this is bug 1302215.
>>>
>>> I wrote a sql script to help with cleanup in this scenario, which you can
>>> find attached to the bug along with a description of how to use it[1].
>>>
>>> However, Rik, before trying that, would you be able to run the attached
>>> script [2] (or just the db query within) and forward the output to me? I'd
>>> like to make sure everything looks as it should before modifying the db
>>> directly.
> 
> I ran the following query on the engine database:
> 
> select images.* from images join snapshots ON (images.vm_snapshot_id =
> snapshots.snapshot_id)
> join vm_static on (snapshots.vm_id = vm_static.vm_guid)
> where vm_static.vm_name = 'lena' and snapshots.description='before
> jessie upgrade';
> 
> The resulting output is:
> 
>               image_guid              |     creation_date      |    size
>     |               it_guid                |               parentid
>           | images
> tatus |        lastmodified        |            vm_snapshot_id
>   | volume_type | volume_format |            image_group_id            |
>         _create_da
> te          |         _update_date          | active |
> volume_classification
> --------------------------------------+------------------------+-------------+--------------------------------------+--------------------------------------+-------
> ------+----------------------------+--------------------------------------+-------------+---------------+--------------------------------------+-------------------
> ------------+-------------------------------+--------+-----------------------
>  24d78600-22f4-44f7-987b-fbd866736249 | 2015-05-19 15:00:13+02 |
> 34359738368 | 00000000-0000-0000-0000-000000000000 |
> 00000000-0000-0000-0000-000000000000 |
>     4 | 2016-01-30 08:45:59.998+01 |
> 4b4930ed-b52d-47ec-8506-245b7f144102 |           1 |             5 |
> b2390535-744f-4c02-bdc8-5a897226554b | 2015-05-19 15:00:1
> 1.864425+02 | 2016-01-30 08:45:59.999422+01 | f      |                     1
> (1 row)
> 
> Regards,
> 
> Rik
> 
> 
>>>
>>> Thanks,
>>> Greg
>>>
>>> [1] https://bugzilla.redhat.com/show_bug.cgi?id=1302215#c13
>>> (Also note that the engine should be stopped before running this.)
>>>
>>> [2] Arguments are the ovirt db name, db user, and the name of the vm you
>>> were performing live merge on.
>>>
>>>
>>>> Thanks,
>>>> michal
>>>>
>>>>>
>>>>>
>>>>> Regards,
>>>>>
>>>>> Rik
>>>>>
>>>>> On 02/03/2016 10:26 AM, Rik Theys wrote:
>>>>>>
>>>>>> Hi,
>>>>>>
>>>>>> I created a snapshot of a running VM prior to an OS upgrade. The OS
>>>>>> upgrade has now been succesful and I would like to remove the snapshot.
>>>>>> I've selected the snapshot in the UI and clicked Delete to start the
>>>>>> task.
>>>>>>
>>>>>> After a few minutes, the task has failed. When I click delete again on
>>>>>> the same snapshot, the failed message is returned after a few seconds.
>>>>>>
>>>>>>>  From browsing through the engine log (attached) it seems the snapshot
>>>>>>
>>>>>> was correctly merged in the first try but something went wrong in the
>>>>>> finalizing fase. On retries, the log indicates the snapshot/disk image
>>>>>> no longer exists and the removal of the snapshot fails for this reason.
>>>>>>
>>>>>> Is there any way to clean up this snapshot?
>>>>>>
>>>>>> I can see the snapshot in the "Disk snapshot" tab of the storage. It has
>>>>>> a status of "illegal". Is it OK to (try to) remove this snapshot? Will
>>>>>> this impact the running VM and/or disk image?
> 

-- 
Rik Theys
System Engineer
KU Leuven - Dept. Elektrotechniek (ESAT)
Kasteelpark Arenberg 10 bus 2440  - B-3001 Leuven-Heverlee
+32(0)16/32.11.07
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