Unable to use Kubuntu 18.10?


New Member
Nov 1, 2018
Hello guys,

I installed the latest ISO (version 5.3-2) of Proxmox VE, and try to install Kubuntu on a VM.

Configuration of the VM is very common : 4GB ram, 2 CPU cores, 50GB or disk space... No other modification of the default settings.
I can start the VM and perform the installation without issue. But after reboot... Black screen.

I can access console by pressing CRTL+MAJ+F2, and it seems that the X server is not able to start, but I'm not good enough in Linux environments to troubleshoot deeper... :(

Note : I tried to change the display from default to Spice dual screen, same issue.
Any known issue ?


Which Kubuntu ISO do you use?

=> use VMware compatible as virtual graphic card
I'm using Kubuntu 18.10.

I don't know why, but I reinstalled Proxmox from the ISO image WITHOUT doing any update, and after selecting SPLICE dual display, everything seems fine... Then I made the updates and everything seems OK. Strange...

I fixed the issue on Manjaro too (I had issue with Spice and dual screen), by running :
pamac install xf86-video-qxl spice-vdagent qemu-guest-agent​

+ editing /etc/X11/xorg.conf.d/90-mhwd.conf, and edit the Device section like that :
Section "Device"
Identifier "XSPICE QXL"
Driver "qxl"
BusID "PCI:0:2:0"
Option "DRI" "true"
Option "NumHeads" "2"
Option "EnableSurfaces" "0"

It might be useful to make documentation about how to use SPICE on the different distro (same for graphic cards to use, depending on the distro).

Anyway thanks for your help. I really appreciate your support, and for sure I'll take a subscription for your services this year if I start to use Proxmox on my server (I'm currently testing it). :)
It might be useful to make documentation about how to use SPICE on the different distro (same for graphic cards to use, depending on the distro).

Glad that you could set your system up, but the place for distribution and version related settings is in the distribution's documentation, not the hypervisor. Spice is not made by Proxmox, it's a common technique.
I understand you point of view... But Proxmox uses Spice too, so it would be good to explain HOW to use it with the main distro, in order to be able to use your product.

More generally, do you think it's normal to have black screen with the default display driver, when installing distro like Kubuntu ? If the default drivers is not working everywhere, it would be good to be informed which driver to chose for which distribution... Because for one person who ask for the forum, 10 or 20 just think "it's not working" and go away without saying a word. :)

I think it would be useful for Proxmox to give as much information as they can about how to use their product, which includes how to use it to install Windows VM, Mac OS VM, and Linux VM. And this includes what to install to use their different features.

Anyway it's just a personal opinion. They are free to ignore it if they don't agree ! :D


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