Ubuntu
libvirt package

virsh create-snapshot fails

Bug #1096125 reported by Riccardo Casatta on 2013-01-04

This bug report is a duplicate of: Bug #1004606: virsh create-snapshot fails to create external snapshot (blockdev-snapshot-sync fails in json monitor). Edit Remove

This bug affects 7 people

Affects		Status	Importance	Assigned to	Milestone
	libvirt (Ubuntu)	Triaged	High	Unassigned

Bug Description

Hello,

i have a plain installation of Ubuntu 12.10 server,
i installed package ubuntu-virt-server and added the user to the kvm and libvirtd group. (qemu-kvm 1.2 libvirt 0.9.13)
After that i can run kvm virtual machines.

Now i am trying to get a snapshot of the disk (first step to achieve live backup of virtual machines)
virsh snapshot-create-as [vmname] snapshot1 "snapshot" --disk-only --atomic

but i am getting the following error:
error: internal error unable to execute QEMU command 'transaction': Could not open '/var/lib/libvirt/images/ubu1204.snapshot1'

(i even tryed with permission 777 )

Revision history for this message

Launchpad Janitor (janitor) wrote on 2013-01-04:

Status changed to 'Confirmed' because the bug affects multiple users.

Changed in kvm (Ubuntu):
status:	New → Confirmed

Serge Hallyn (serge-hallyn) on 2013-01-07

Changed in kvm (Ubuntu):
importance:	Undecided → Medium

Revision history for this message

Serge Hallyn (serge-hallyn) wrote on 2013-01-07:

I don't believe this is due to apparmor. However there certainly is an apparmor bug, as running virsh snapshot-create-as causes the /etc/apparmor.d/libvirt/<test1-uuid>.files entry for /var/lib/libvirt/images/test1.img to be replaced by one for

/var/lib/libvirt/images/test1.snapshot1

Revision history for this message

Riccardo Casatta (riccardo-casatta) wrote on 2013-01-08:

Hi Serge,

i made a snapshot after disabling apparmor and it works!

Here are the commands used:

/etc/init.d/apparmor stop
update-rc.d -f apparmor remove
reboot now
virsh snapshot-create-as ubu-server-64-10.04.3 snap1 --disk-only

So i changed the target package of the bug to apparmor

Thank you again

affects:

kvm (Ubuntu) → apparmor (Ubuntu)

Revision history for this message

Serge Hallyn (serge-hallyn) wrote on 2013-01-08:

Thanks, Riccardo. That actually points to libvirt (in particular virt-aa-helper) being the problem.

affects:	apparmor (Ubuntu) → libvirt (Ubuntu)
Changed in libvirt (Ubuntu):
importance:	Medium → High
status:	Confirmed → In Progress
status:	In Progress → Triaged