On Mon, Apr 25, 2022 at 05:52:09PM +0100, Richard W.M. Jones wrote:

On Mon, Apr 25, 2022 at 04:11:59PM +0100, Richard W.M. Jones wrote:
On Mon, Apr 25, 2022 at 04:40:15PM +0200, Nguetchouang Ngongang Kevin wrote:
I want to achieve the external data file creation

"qemu-img create -o data_file_raw=on,data_file=path/to/file"

but there is no way to specify those options while using virt-builder.

Interesting - I had no idea about this feature before.

At the moment it's not possible to do this within virt-builder,
without patching virt-builder. I guess maybe you can post-convert the
file after virt-builder has run?

I grepped the source of virt-install and it doesn't seem like it has
support either. Nor does libvirt.

It should be possible to use virt-customize on these special qcow2
files, although I didn't try it.

I talked to Kevin and apparently this feature was added to qemu to

(I mean Kevin Wolf)

support a particular downstream project (oVirt), but in the end they
didn't use it and also support was never added to libvirt. So it
doesn't particularly sound like this is a well tested or widely used
feature ...

Rich.

--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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