openstack team mailing list archive

[Pádraig Brady <P@xxxxxxxxxxxxxx>]

On 06/08/2012 09:20 AM, Fredric Morenius wrote:
> Hello All,
> 
> An update on the use of the qemu-nbd/kpartx based solution to inject files into VM images:
> 
> After some more testing it has turned out that injection into the UEC version of CirrOS (this: https://launchpad.net/cirros/trunk/0.3.0/+download/cirros-0.3.0-x86_64-uec.tar.gz) works fine, but injection into the qcow2 version of the image produces the error given in the previous mail, so there seems to be robustness problems with these tools.

Yes it's seems that qemu-nbd has issues with this image?

# rpm -qf $(which qemu-nbd)
qemu-common-1.0-17.fc17.x86_64
# qemu-img info cirros-0.3.0-x86_64-disk.img
image: cirros-0.3.0-x86_64-disk.img
file format: qcow2
virtual size: 39M (41126400 bytes)
disk size: 9.3M
cluster_size: 65536
# qemu-nbd -c /dev/nbd15 $PWD/cirros-0.3.0-x86_64-disk.img
# ls -la /sys/block/nbd15/pid
-r--r--r--. 1 root root 4096 Jun  8 10:19 /sys/block/nbd15/pid
# kpartx -a /dev/nbd15
device-mapper: resume ioctl on nbd15p1 failed: Invalid argument
create/reload failed on nbd15p1

If I convert to raw with qemu-img, I can mount loopback fine.

cheers,
Pádraig.