Re: [Qemu-discuss] libvirt live migration, qcow2 image, nbd server

[Jakob Bohm]

On 13/02/2015 03:41, Edward Young wrote:

Hi all,

When I live migrate a vm using 

"migrate --live --copy-storage-all mig-vm qemu+ssh://192.168.1.3/system tcp://192.168.1.3"

I got the following error

             WARNING: Image format was not specified for 'nbd://node2:49155/drive-virtio-disk0' and probing guessed raw.

258          Automatically detecting the format is dangerous for raw images, write operations on block 0 will be restricted.

259          Specify the 'raw' format explicitly to remove the restrictions.

From the error itself, I can tell that nbd server treat this image as raw, rather than qcow2. My platform is libvirt+qemu. the image type of this vm is indeed qcow2. I do not know how to let nbd know this image format.

Thanks!

Ed

Are you sure it is not saying that the image served by qemu (on the destination) based on *decoding* the qcow2 disk is treated as a raw image, which it probably is, with the serving qemu instance mapping the "raw" read/writes to proper qcow2 operations?

Just guessing of cause.

Enjoy

Jakob
-- 
Jakob Bohm, CIO, Partner, WiseMo A/S.  http://www.wisemo.com
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