Linux guest with spice and multiple displays

XavierBlak

New Member
Jun 9, 2011
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I'm attempting to get multiple display to work on a linux vm using the spice viewer. I've tried it with two different linux vms (xbunutu and arch) and I am able to get a single display with out any problem but I'm having trouble getting a second.

Now I know linux as a server os but I'm not really to familiar with linux desktop os, so maybe there is something simple I am missing. I've tried using the different option in the hardware tab for SPICE dual monitors.

I'm using the windows version virt-viewer 2.0 from http://virt-manager.org/download/. Under the View > Displays menu it only gives me the option of Display 1 all the other options are greyed out. From what I've seen online is it should just work and these should be available.

Is anyone using multiple displays on their vms?
 
By the lack of replies I guess this setup isn't too common. I tried the same setup with a windows VM and I was able to get it working fairly easily.

Is there a better option for using a virtualized multiple monitor setup over a local network?
 
No not that common, I think, but the SPICE manual also states that windows and Linux differ.

When using Spice, it’s possible to use multiple monitors. For that, the guest must have multiple QXL devices (for Windows guests), or a single QXL device configured to support multiple heads (for Linux guests).
[...]
If you are using a new enough distribution (for example Fedora 19), and if your virtual machine already has a QXL device, you should not need to make any changes in the hyper-visor settings

You should be able to use it with only one qxl device and then adding new displays via your client, AFAIK.
 
Just as a follow up to this thread I tried installing Fedora 22 Workstation. The multi-monitor option was available with that. I'm not sure what the difference is but it works out of the box with Fedora.

Thanks for your help.
 
Good to hear, I tried it yesterday another time with latest Ubuntu and although i saw the 4 Virtual screens on the guest machine with xrandr, my SPICE client (virt-viewer) refuses to open an second window. Looks like it's really a bit distribution/client dependent.
 
In Proxmox KVM, I am doing everything properly, have spice-vdagent installed in VM Ubuntu 20.04 LTS Desktop (gnome), but still the system won't see in display settings any extra monitor, and clicking display 2 in remote-viewer doesn't do anything.

I've seen that people have had this problem with different Ubuntu versions (ranging probably to even 16.04 LTS already then), and I have encountered that this might be problem with HWE kernel, so perhaps reinstalling to GA kernel can fix the problem:

https://stafwag.github.io/blog/blog...resolution-on-a-kvm-virtual-machine-with-qxl/

https://askubuntu.com/a/1011440/702332

I haven't tried that but I will give it a shot some day in the future.

I also reported the case here and in other places:
https://forum.proxmox.com/threads/spice-dual-monitor-from-windows-7-guest.52296/
 
Last edited:
I was having a similar issue with a kali vm in proxmox. The single monitor worked perfect in the spice client (remote-viewer.exe), but when adding another display, the second display would be black or unresponsive. I then tested spice on an Ubuntu 22.04 vm and it worked fine with multiple monitors. I noticed that the xserver-xorg-video-qxl was installed on the ubuntu machine by default but didn't exist on my kali machine. After installing the xserver-xorg-video-qxl package from the debian unstable repository, multiple monitors worked perfectly in kali.
 

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