QXL Video Mode & USB Redirector won't work via VMM in KVM/Libvirt installation on Micro-OS.

Hi everyone,

I have recently decided to use OpenSUSE Micro-OS as my Hypervisor of choice for a KVM/Libvirt Server due to it’s versatility, read only file system, and small footprint. I have installed the KVM server patterns (patterns-server-kvm_server & patterns-server-kvm_tools) on the Micro-OS server which allows me to connect to it remotely via Virtual Machine Manager which is going to be my preferred method of creating, and working with the mostly Windows KVM VMs which are going to ultimately run on this server.

Everything seems to be working fine other than two issues which are stopping me from using the setup to it’s full potential.

  • Issue 01: QXL Video Mode.

I cannot seem to be able to chose QXL video mode under Virtual Hardware Details > Video > Details tab of the virtual machine being created. The error message shown by the system is:

Error changing VM configuration: unsupported configuration: domain configuration does not support 'video model' value 'qxl'

This is while I have another server running Tumbleweed, with KVM server patterns installed, which has no issue adding the QXL video mode to the new VMs being created. What is more is that both the Micro-OS, and the Tumbleweed installations have the QEMU version 5.1.0 installed which made me believe that they should both behave the same.

In this case choosing different video modes (Bochs, VGA & Virtio) work, but won’t allow for the use of driver compatibility features such as “fit to window size” that QXL provides with additional drivers.

  • Issue 02: SPICE USB Redirection

In the same way, if the new VMs have SPICE USB Redirection the system will spit out another error which will prevent the creation of the VM. The error reads;

Error starting domain: unsupported configuration: USB redirection is not supported by this version of QEMU

Interestingly, the adding of the USB Host Device to the VM (Virtual Hardware Details > Add hardware > USB Host Device) works in connecting the USB (storage) device to the VM once setup, but then again it is very inconvenient since the system has to be shutdown everytime the USB device is to be disconnected, and a new one connected.

Conversely, the same can be easily achieved on the Tumbleweed server with the KVM pattern installed which makes me believe that there has got to be something I am missing in the Micro-OS setup, but I cannot find it no matter where I look.

It might be helpful to add that the VMs being made use UEFI firmware instead of BIOS with the Q35 chipset.

Any help is much appreciated

Thanks to Richard Brown’s reply on the mailing list I now have a fix and know the reason why this happened.

The issue seems to have to do with a couple of the sub packages (qemu-hw-usb-redirect & qemu-hw-display-qxl) not being pulled as intended by the virtualization team when installing the KVM patterns on the Micro-OS installation.

The easy workaround would be to manually install the said packages using:

transactional-update pkg in qemu-hw-usb-redirect qemu-hw-display-qxl

which will fix the issue.

At the request of Richard I have also filed a bug report on this issue so that it can hopefully get addressed in the future.

Cheers.