Open Stack

The actual user workflow is:

 1 - User creates a volume(s)
 2 - User attach volume to instance
 3 - User creates a snapshot
 4 - Something happens causing the need of a revert
 5 - User creates a volume(s) from the snapshot(s)
 6 - User detach old volumes
 7 - User attach new volumes (and pray so they get the same id) - Nova,
should have the ability to honor supplied device names (vdc, vdd, etc),
which not always happen[1]. But, does the volume keep the same UUID in the
system? Several application use that to boot.

The suggested workflow would be simpler for a user POV:

 1 - User creates a volume(s)
 2 - User attach volume to instance
 3 - User creates a snapshot
 4 - Something happens causing the need of a revert
 5 - User revert snapshot(s)


 [1] https://goo.gl/Kusfne

On Fri, Apr 8, 2016 at 5:07 AM, Ivan Kolodyazhny <e0ne at e0ne.info> wrote:

> Hi Chenzongliang,
>
> I still don't understand what is difference between proposed feature and
> 'restore volume from snapshot'? Could you please explain it?
>
> Regards,
> Ivan Kolodyazhny,
> http://blog.e0ne.info/
>
> On Thu, Apr 7, 2016 at 12:00 PM, Chenzongliang <chenzongliang at huawei.com>
> wrote:
>
>> Dear Cruz:
>>
>>
>>
>>          Thanks for you kind support, I will review the previous spec
>> according to the following links.  May be more user scenario we should
>> considered,such as backup,create volume from snapshot,consistency group and
>> etc,we will spend some time to gather
>>
>> the user's scenarios and determin what to do next step.
>>
>>
>>
>> Sincerely,
>>
>> zongliang chen
>>
>>
>>
>> *发件人:* Erlon Cruz [mailto:sombrafam at gmail.com]
>> *发送时间:* 2016年4月5日 2:50
>> *收件人:* OpenStack Development Mailing List (not for usage questions)
>> *抄送:* Zhangli (ISSP); Shenhong (C)
>> *主题:* Re: [openstack-dev] [Cinder] About snapshot Rollback?
>>
>>
>>
>> Hi Chen,
>>
>>
>>
>> Not sure if I got you right but I brought this topic in #openstack-cinder
>> some days ago. The idea is to be able to rollback a snapshot in Cinder.
>> Today what is possible to do is to create a volume from a snapshot. From
>> the user point of view, this is not ideal, as there are several cases, if
>> not the majority of, that the purpose of the snapshot is to revert to a
>> desired state, and not keep the original volume. For some backends, keeping
>> the original volume means space consumption. This space problem becomes
>> bold when we think about consistency groups. For consistency groups, some
>> backends might have to copy an entire filesystem for each snapshot,
>> consuming space and time. So, I think it would be desired to have the
>> ability to revert snapshots.
>>
>>
>>
>> I know there have been efforts in the past[1] to implement that, but for
>> some reason the work was stopped. If you want to retake the effort please
>> create a spec[2]  sol everybody can provide feedback.
>>
>>
>>
>> Erlon
>>
>>
>>
>>
>>
>> [1]
>> https://blueprints.launchpad.net/cinder/+spec/cinder-volume-rollback-snapshot
>>
>> [2] https://github.com/openstack/cinder-specs
>>
>>
>>
>> On Thu, Mar 24, 2016 at 6:09 AM, Chenzongliang <chenzongliang at huawei.com>
>> wrote:
>>
>> Hi all:
>>
>>     We are condering add a fucntion rollback_snapshot when we use backup.
>> In the end user's scenario. If a vm fails, we hope that we can use snapshot
>> to to recovery the volume's data.
>>
>>     Beacuse it can quickly recovery our vm. But if we use the remote data
>> to recovery. We will spend more time.
>>
>>     But i'm not sure if the data was recoveried from the backend. whether
>> the host need to rescan the volumes? At the same time. If a volume have
>> been extended, whether it can be roolback?
>>
>>
>>
>>    I want to know whether the topic have been discussed or have other
>> recommendations to us?
>>
>>
>>
>>    Thanks
>>
>>
>> __________________________________________________________________________
>> OpenStack Development Mailing List (not for usage questions)
>> Unsubscribe:
>> OpenStack-dev-request at lists.openstack.org?subject:unsubscribe
>> http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
>>
>>
>>
>> __________________________________________________________________________
>> OpenStack Development Mailing List (not for usage questions)
>> Unsubscribe:
>> OpenStack-dev-request at lists.openstack.org?subject:unsubscribe
>> http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
>>
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstack.org/pipermail/openstack-dev/attachments/20160411/3a03813f/attachment.html>