Re: [libvirt] [PATCH 1/2] rbd: Implement wiping RBD volumes using rbd_discard()

On 23-12-15 10:45, Daniel P. Berrange wrote: > On Wed, Dec 23, 2015 at 10:29:04AM +0100, Wido den Hollander wrote: >> This allows user to use the volume wiping functionality of the libvirt >> storage driver. >> >> All data from the volume will be wiped by calling rbd_discard() in chunks of the >> underlying object and stripe size inside Ceph. >> >> This will ensure all data is zeroed and leaves the user with a completely empty volume >> ready for use again. > > Based on the name 'rbd_discard' it sounds like this is going to call > TRIM/DISCARD on the underlying storage too ? If so, then I don't think > that this is an appropriate approach for this API. The virStorageVolWipe > API should clear the data, *without* having any effect on the storage of > the API - ie we don't want to discard underling storage blocks as a > side effect > Afaik it zeroes/trims all the RBD objects on the Ceph cluster, but it doesn't TRIM the lower SSD on it's turn. So it will send these calls to Ceph/RBD and it will zero all the data of that specific volume. A rather simple way to get rid of the data in a volume.