[virt-tools-list] Error when adding CD-ROM drives to a Q35 machine (and a workaround and a feature request)

[Gizmo Chicken]

When creating a Windows 7 guest on a Q35 machine, I attempted to add
one VirtIO data drive for the guest OS, one CD-ROM drive for the
installation media and a second CD-ROM drive for the VirtIO drivers
that must be installed prior to installing Windows 7 on a VirtIO
drive. Unfortunately, when hitting “begin installation” I received an
error message. (See below for details.)

In essence, the error message says that I had attempted to exceed the
maximum number of drives permitted for one IDE bus. (Actually, more
drives could be added to the single bus, but not in the way
virt-manager attempts to add them.)

So I added a SATA bus and I tried to add the additional CD-ROMs to
that SATA bus, but couldn't find an explicit option to do so directly.

Finally, after first adding the IDE CD-ROMs (but before hitting “begin
installation”), I went to “advanced options” for each CD-ROM and typed
“sata” (in lower case, without the quotes) next to “Disk bus” (in
place of IDE) for each CD-ROM, and then hit “begin installation” to
create the guest. Doing so allowed me to add two SATA CD-ROMs to a Q35
machine using virt-manager.

FEATURE REQUEST: Please provide a more direct means for adding SATA
CD-ROM drives when creating a guest machine. And ideally, SATA CD-ROMs
should be the default when using a Q35 machine.


~~~~~

Here are the details of the above mentioned error message:

Error starting domain: internal error: process exited while connecting
to monitor: 2015-01-26T01:42:12.626044Z qemu-system-x86_64: -device
ide-cd,bus=ide.0,unit=1,drive=drive-ide0-0-1,id=ide0-0-1: Can't create
IDE unit 1, bus supports only 1 units

2015-01-26T01:42:12.626092Z qemu-system-x86_64: -device
ide-cd,bus=ide.0,unit=1,drive=drive-ide0-0-1,id=ide0-0-1: Device
initialization failed.

2015-01-26T01:42:12.626111Z qemu-system-x86_64: -device
ide-cd,bus=ide.0,unit=1,drive=drive-ide0-0-1,id=ide0-0-1: Device
'ide-cd' could not be initialized

Traceback (most recent call last):

File "/usr/share/virt-manager/virtManager/asyncjob.py", line 89, in cb_wrapper

callback(asyncjob, *args, **kwargs)

File "/usr/share/virt-manager/virtManager/asyncjob.py", line 125, in tmpcb

callback(*args, **kwargs)

File "/usr/share/virt-manager/virtManager/domain.py", line 1360, in startup

self._backend.create()

File "/usr/lib/python2.7/dist-packages/libvirt.py", line 999, in create

if ret == -1: raise libvirtError ('virDomainCreate() failed', dom=self)

libvirtError: internal error: process exited while connecting to
monitor: 2015-01-26T01:42:12.626044Z qemu-system-x86_64: -device
ide-cd,bus=ide.0,unit=1,drive=drive-ide0-0-1,id=ide0-0-1: Can't create
IDE unit 1, bus supports only 1 units

2015-01-26T01:42:12.626092Z qemu-system-x86_64: -device
ide-cd,bus=ide.0,unit=1,drive=drive-ide0-0-1,id=ide0-0-1: Device
initialization failed.

2015-01-26T01:42:12.626111Z qemu-system-x86_64: -device
ide-cd,bus=ide.0,unit=1,drive=drive-ide0-0-1,id=ide0-0-1: Device
'ide-cd' could not be initialized