[libvirt-users] Error Attaching Seventh VirtIO-SCSI Device to Guest

[Osier Yang]

On 04/09/13 09:34, McEvoy, James wrote:
> I have run into a problem attempting to attach the seventh virtio-scsi device to a RHEL 6.4 Guest from a RHEL 6.4 host running libvirt version 0.10.2-18.
> I have a guest that is running RHEL6.4 where I can attach disks sda(boot), sdb, sdc, sdd, sde and sdf but when I try to attach sdg the virsh attach-disk command fails with the error:
> error: Failed to attach disk
> error: internal error Unable to determine model for scsi controller
>
> I logged Bug 996327  on this issue including an attached script to repro the bug but there has been no activity on that bug so far.

I took the bug.

>
> This is the results when attaching virtio-scsi disks in a loop. Sdf is attached but sdg fails.
>
> virsh attach-disk --domain UEM004n1 --source /dev/GuestVols/UEM004-5 --target sdf --cache none --type disk --config --wwn 1fc7058865439717 --serial c7d11fc7058865439717 --shareable
> Disk attached successfully
>
> Vol UEM004-6 created
> virsh attach-disk --domain UEM004n1 --source /dev/GuestVols/UEM004-6 --target sdg --cache none --type disk --config --wwn 4d3ddb9d15b05e7e --serial 62fd4d3ddb9d15b05e7e --shareable
>
> error: Failed to attach disk
> error: internal error Unable to determine model for scsi controller

It looks odd,  It looks to me there is new scsi controller is generated
automatically by libvirt when the 6th volume is attaching to the domain,
since for narrow SCSI bus, we allow 7 unit for each SCSI controller. But
it's strange that it couldn't get a default model for the new SCSI 
controller.

Can you get the devices your qemu supports by:

     $ qemu-kvm -device ?

And attach your domain conf?

Either in the list or in the bug is fine.

Osier