[openstack-dev] [nova] Two questions about 'backup' API
wingwj at gmail.com
Fri Jun 27 01:58:22 UTC 2014
Hi Vish, thanks for your reply.
About Q1, I mean that Nova doesn't have extra processions/works for
'daily'/'weekly' than other backup_types like '123'/'test'.
The 'daily' & 'weekly' don't have unique places in the API than any other
But we gave them as examples in code comments especially in novaclient.
A few users asked me why their instances were not backup-ed automatically,
they thought we have a timing task to do this if the 'backup_type' equals
to 'daily'/'weekly' because we prompt them to use it..
Therefore, it's useless and inclined to make confusion for this API IMO. No
need to show them in code comments & novaclient.
P.S. So maybe 'backup_name'/'backup_tag' is a better name, but we can't
modify the API for compatibility..
On Fri, Jun 27, 2014 at 5:20 AM, Vishvananda Ishaya <vishvananda at gmail.com>
> On Jun 26, 2014, at 5:07 AM, wu jiang <wingwj at gmail.com> wrote:
> > Hi all,
> > I tested the 'backup' API recently and got two questions about it:
> > 1. Why 'daily' & 'weekly' appear in code comments & novaclient about
> 'backup_type' parameter?
> > The 'backup_type' parameter is only a tag for this backup(image).
> > And there isn't corresponding validation for 'backup_type' about these
> two types.
> > Moreover, there is also no periodic_task for 'backup' in compute host.
> > (It's fair to leave the choice to other third-parts system)
> > So, why we leave 'daily | weekly' example in code comments and
> > IMO it may lead confusion that Nova will do more actions for
> 'daily|weekly' backup request.
> The tag affects the cleanup of old copies, so if you do a tag of ‘weekly’
> the rotation is 3, it will insure you only have 3 copies that are tagged
> You could also have 3 copies of the daily tag as well.
> > 2. Is it necessary to backup instance when 'rotation' is equal to 0?
> > Let's look at related codes in nova/compute/manager.py:
> > # def backup_instance(self, context, image_id, instance,
> backup_type, rotation):
> > #
> > # self._do_snapshot_instance(context, image_id, instance,
> > # self._rotate_backups(context, instance, backup_type, rotation)
> > I knew Nova will delete all backup images according the 'backup_type'
> parameter when 'rotation' equals to 0.
> > But according the logic above, Nova will generate one new backup in
> _do_snapshot_instance(), and delete it in _rotate_backups()..
> > It's weird to snapshot a useless backup firstly IMO.
> > We need to add one new branch here: if 'rotation' is equal to 0, no need
> to backup, just rotate it.
> That makes sense I suppose.
> > So, what's your opinions? Look forward to your suggestion.
> > Thanks.
> > WingWJ
> > _______________________________________________
> > OpenStack-dev mailing list
> > OpenStack-dev at lists.openstack.org
> > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
> OpenStack-dev mailing list
> OpenStack-dev at lists.openstack.org
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the OpenStack-dev