Re: [libvirt-users] virsh snapshot-create and blockcopy

On 06/10/2013 01:20 PM, Thomas Stein wrote: > Am 10.06.13 09:07, schrieb Kashyap Chamarthy: >> On 06/09/2013 02:46 PM, Thomas Stein wrote: >>> Hello. >>> >>> I just tried the following: >>> >>> virsh dumpxml --security-info gentoo-template > gentoo-template.xml >>> virsh snapshot-create gentoo-template >>> virsh undefine gentoo-template >> >> Wait - is that really the command you used after "snapshot-create" ? > >> Because: You cannot undefine a guest with a snapshot without first deleting its metadata >> >> To cleanly delete, maybe you should've done: >> >> $ virsh snapshot-delete --domain gentoo-template SNAPSHOTID --metadata > > Did that. But that deletes that snapshot too, no? Yes. (I just understood what you wanted to do). Noted my details below. > >> >>> virsh blockcopy gentoo-template vda >>> /opt/virt-backup-blockcopy/gentoo-template/gentoo-template.qcow2 --wait --verbose --finish >>> virsh define gentoo-template.xml >> >> Can you also paste the output of: >> >> $ qemu-img info --backing-chain \ >> /opt/virt-backup-blockcopy/gentoo-template/gentoo-template.qcow2 > > hn ~ # qemu-img info --backing-chain > /opt/virt-backup-blockcopy/gentoo-template/gentoo-template.qcow2 > image: /opt/virt-backup-blockcopy/gentoo-template/gentoo-template.qcow2 > file format: qcow2 > virtual size: 130G (139586437120 bytes) > disk size: 30G > cluster_size: 65536 > > Just to make myself clear. I want to backup the qcow image /with/ the > internal snapshot. Is that even possible with blockcopy? Let's try. I just did the below test (also I noted it in the URL below) # Take an (internal) snapshot when the guest was shutdown

$ virsh snapshot-list fed18 Name Creation Time State ------------------------------------------------------------ 1370847718 2013-06-10 12:31:58 +0530 shutoff # Start the guest $ virsh start fed18 # Undefine the guest while it is running - this will # make the guest transient (libvirt expects it to be 'transient') $ virsh undefine fed18 Domain fed18 has been undefined # List the guest root@~$ virsh list Id Name State ---------------------------------------------------- 3 fed18 running $ # Do blockcopy (it's only when the guest is "live") $ virsh blockcopy --domain fed18 vda \ /export/backup/images/fed18.qcow2 --wait --finish --verbose Block Copy: [ 100 %] # Query the info of original image: =========== root@~$ qemu-img info --backing-chain /var/lib/libvirt/images/el6box1.qcow2 image: /var/lib/libvirt/images/el6box1.qcow2 file format: qcow2 virtual size: 10G (10737418240 bytes) disk size: 1.2G cluster_size: 65536 Snapshot list: ID TAG VM SIZE DATE VM CLOCK 1 1370853048 0 2013-06-10 14:00:48 00:00:00.000 =========== $ qemu-img snapshot -l /var/lib/libvirt/images/el6box1.qcow2 Snapshot list: ID TAG VM SIZE DATE VM CLOCK 1 1370853048 0 2013-06-10 14:00:48 00:00:00.000 =========== # Query info of the backup: =========== $ qemu-img info --backing-chain /export/backup/images/el6box1-back.qcow2 image: /export/backup/images/el6box1-back.qcow2 file format: qcow2 virtual size: 10G (10737418240 bytes) disk size: 10G cluster_size: 65536 =========== $ qemu-img snapshot -l /export/backup/images/el6box1-back.qcow2 =========== Hm, from what it looks, it doesn't appear to preserve the internal snapshot.. > >> http://kashyapc.fedorapeople.org/virt/lc-2012/live-backup-with-blockcopy.txt >>