On Thu, Jun 14, 2018 at 11:13:22AM +0200, Thomas Goirand wrote: > Hi, > > When using cinder-backup, it first makes a snapshot, then sends the > backup wherever it's configured. The issue is, to perform a backup, one > needs to make a snapshot of a volume, meaning that one needs the size of > the volume as empty space to be able to make the snapshot. > > So, let's say I have a cinder volume of 1 TB, this mean I need 1 TB as > empty space on the volume node so I can do a backup of that volume. > > My question is: is there a way to tell cinder to reserve an amount of > space for this kind of operation? The only thing I saw was > reserved_percentage, but this looks like for thin provisioning only. If > this doesn't exist, would such new option be accepted by the Cinder > community, as a per volume node option? Or should we do it as a global > setting? >
I don't believe we have this as a setting anywhere today. It would be best as a per-backend (or backend_defaults) setting as some backends can create volumes from snapshots without consuming any extra space, while others like you point out with LVM needing to allocate a considerable amount of space. Maybe someone else can chime in if they are aware of another way this is already being handled, but I have not had to deal with it, so I'm not aware of anything. __________________________________________________________________________ OpenStack Development Mailing List (not for usage questions) Unsubscribe: [email protected]?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
