[fedora-virt] How to use virtio-scsi on F17 host and F17 guest

[Cole Robinson]

On 06/06/2012 12:30 PM, Gianluca Cecchi wrote:
> Hello,
> reading here:
> https://fedoraproject.org/wiki/Features/virtio-scsi
> 
> it should be possible to use virtio-scsi, even if not completely
> integrated in libvirt.
> And installation would require this part for the hard disk:
> 
> -drive if=none,id=hd,file=/path/to/test.img -device
> virtio-scsi-pci,id=scsi -device scsi-hd,drive=hd
> 
> I have now an F17 host (kernel 3.3.7) and F17 guest (3.4.0) configured
> with a virtio_blk disk
> guest definition for the disk is this:
>     <disk type='file' device='disk'>
>       <driver name='qemu' type='qcow2'/>
>       <source file='/var/lib/libvirt/images/f17.img'/>
>       <target dev='vda' bus='virtio'/>
>       <address type='pci' domain='0x0000' bus='0x00' slot='0x06'
> function='0x0'/>
>     </disk>
> 
> Can I change it with "virsh edit" so that I can use virtio-scsi inside
> guest and test?
> What would be the xml snippet for it? Or do I have to use also a
> wrapper to start qemu-kvm with particular options as during install?
> 

It looks like you want to add :

<controller type='scsi' index='0' model='virtio-scsi'/>

Then in change that <target line to

<target dev='sda' bus='scsi'/>

Problem is this will change the disk device node in the guest from vda to sda,
so could cause mounting problems.

- Cole