Le 12/06/2019 à 16:01, Jason Dillaman a écrit :
On Wed, Jun 12, 2019 at 9:50 AM Rafael Diaz Maurin <Rafael.DiazMaurin@xxxxxxxxxxxxxxx> wrote:Hello Jason, Le 11/06/2019 à 15:31, Jason Dillaman a écrit :4- I export the snapshot from the source pool and I import the snapshot towards the destination pool (in the pipe) rbd export-diff --from-snap ${LAST-SNAP} ${POOL-SOURCE}/${KVM-IMAGE}@${TODAY-SNAP} - | rbd -c ${BACKUP-CLUSTER} import-diff - ${POOL-DESTINATION}/${KVM-IMAGE}What's the actual difference between the "rbd diff" outputs? There is a known "issue" where object-map will flag an object as dirty if you had run an fstrim/discard on the image, but it doesn't affect the actual validity of the data.The feature discard=on is activated, and qemu-guest-agent is running on the guest. Here are the only differences between the 2 outputs of the "rbd diff --format plain" (image source and image destination) : Offset Length Type 121c121 < 14103347200 2097152 data --- > 14103339008 2105344 data 153c153 < 14371782656 2097152 data --- > 14369685504 4194304 data 216c216 < 14640218112 2097152 data --- > 14638120960 4194304 data 444c444 < 15739125760 2097152 data --- > 15738519552 2703360 data And the hashes of the exports are identical (between source and destination) : rbd -p ${POOL-SOURCE} export ${KVM-IMAGE}@${TODAY-SNAP} - | md5sum => ee7012e14870b36e7b9695e52c417c06 rbd -c ${BACKUP-CLUSTER} -p ${POOL-DESTINATION} export ${KVM-IMAGE}@${TODAY-SNAP} - | md5sum => ee7012e14870b36e7b9695e52c417c06 So do you think this can be caused by the fstrim/discard feature.You said you weren't using fstrim/discard.
In fact, the daemon fstrim is not enabled in the guest, but... in proxmox I set the option discard=on and maybe I ran fstrim once by hard testing...
If you export both images and compare those image extents where the diffs are different, is it just filled w/ zeroes?
I can't find how to to compare if the diffs of the extends are filled by w/ zeros.
However I finally succeed getting identical the "rbd diff " hashes with the option "--whole-object" like this :
HASH source :rbd diff --from-snap <YESTERDAY> <POOL>/<IMAGE>@<TODAY> --format json --whole-object | md5sum | cut -d ' ' -f 1
Hash destinationrbd -c <cluster-destination.conf> diff --from-snap <YESTERDAY> <POOL>/<IMAGE>@<TODAY> --format json --whole-object | md5sum | cut -d ' ' -f 1
Best regards, Rafael -- Rafael Diaz Maurin DSI de l'Université de Rennes 1 Pôle Infrastructures, équipe Systèmes 02 23 23 71 57
Attachment:
smime.p7s
Description: Signature cryptographique S/MIME
_______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com