[Libguestfs] Changing a given image from virtio-blk to virtio-scsi

[Richard W.M. Jones]

On Tue, Jul 19, 2016 at 02:29:11PM +0300, Yaniv Kaul wrote:
> Does it make more sense to just use virt-builder and build it from scratch?
> I did not find where in virt-builder I can actually specify virtio-scsi as
> the type.

virt-builder images should boot on virtio-scsi "out of the box",
certainly the x86-64 ones.

If you like you can check what drivers are supported by the initrd
like this:

$ virt-builder --arch x86_64 fedora-23
$ virt-get-kernel -a fedora-23.img 
download: /boot/vmlinuz-4.4.6-300.fc23.x86_64 -> ./vmlinuz-4.4.6-300.fc23.x86_64
download: /boot/initramfs-4.4.6-300.fc23.x86_64.img -> ./initramfs-4.4.6-300.fc23.x86_64.img
$ zcat initramfs-4.4.6-300.fc23.x86_64.img | cpio -it | grep virtio
usr/lib/modules/4.4.6-300.fc23.x86_64/kernel/drivers/block/virtio_blk.ko.xz
usr/lib/modules/4.4.6-300.fc23.x86_64/kernel/drivers/char/hw_random/virtio-rng.ko.xz
usr/lib/modules/4.4.6-300.fc23.x86_64/kernel/drivers/char/virtio_console.ko.xz
usr/lib/modules/4.4.6-300.fc23.x86_64/kernel/drivers/scsi/virtio_scsi.ko.xz
usr/lib/modules/4.4.6-300.fc23.x86_64/kernel/drivers/virtio
usr/lib/modules/4.4.6-300.fc23.x86_64/kernel/drivers/virtio/virtio.ko.xz
usr/lib/modules/4.4.6-300.fc23.x86_64/kernel/drivers/virtio/virtio_pci.ko.xz
usr/lib/modules/4.4.6-300.fc23.x86_64/kernel/drivers/virtio/virtio_ring.ko.xz
51087 blocks

Hence that particular guest should support booting from virtio-blk or
virtio-scsi.

Rich.

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