Dedicated Keyboard and mouse for virtualbox guest

Hello community,

I am running OpenSuse Tumbleweed 64bit (currently based on 12.2) KDE 4.9.3, fully updated, and virtualbox 4.2.6 installed from on the host. The guest is mageia 2 GNU/Linux KDE 4.8 32bit (guest additions have been installed).

I have plugged into the host two keyboards and two mice, which work concurrently. My host desktop spans over two monitors. I would like to use one mouse and one keyboard for the virtual mashine, while working at the same time with the other mouse and the other keyboard on the host (more than two hands are involved;)).

Has anybody had any success with such a setup?

Thank you and marry Christmas.

PS: I have tried adding USB filters, but this led after a very short while to a hard freeze on the host (more than once).

On 2012-12-24 12:26, Nikos78 wrote:
> Has anybody had any success with such a setup?

I think that you should ask this in a VB forum.

Cheers / Saludos,

Carlos E. R.
(from 11.4, with Evergreen, x86_64 “Celadon” (Minas Tirith))

Thank you Carlos. Considering the numerous replies I got here, I guess I’ ll have to follow your advice. This should not hinder anyone giving an answer here though.

On general principles, this is an odd request(but anyone is entitled to ask)

Ordinarily people want to save physical space so want to share kvm between virtual machines.

On general principles though as you already seem to have discovered if the virt tech supports multiple USB devices, it’s theoretically possible. The problem I see though is that any USB use for kvm (not just VMs) is inherently unstable and for VMs can’t be any better.

I think you will be far happier purchasing some cheap hardware kvm extenders and likely using kvm over IP connecting to your remote machine (which can be a VM) rather than relying on USB.


Well I would be saving physical space by using two keyboards and mice, but only one computer case, for four hands and four eyes.

This sounds interesting, but I do not get it. Why is USB use for kvm inherently unstable? Not flaming, just wondering. Particularly, since e.g. my motherboard offers no alternatives for adding any input devices.

BTW I searched a bit in the virtualbox forums and found some posters with similar requests (though no real solution so far) as well as some people claiming to have done this (but no instructions so far). As I understand it, one solution would be to first add a second pointer to my kde desktop (sounds easy enough). I don’t think the mouse will prove to be very difficult, I have my doubts regarding the keyboard though. But this will have to wait till (early) next year.

PS: Please don’t marry Christmas ;). I meant merry Christmas and hope you had it anyway.

Anyone who has either supported networks for many years or travels between jobs knows to always carry a regular PS/2 Keyboard and Mouse or knows where to get one because USB Keyb and Mse may not fail most of the time, but fail often enough to be a significant consideration.

Over the years, I’ve seen many hardware “mini-stations” which are dedicated to only providing human input to VMs or a single mult-User OS but today I would even consider something like a Raspberry Pi (which only costs $25 for a bare board and practically all ready to go out of the box). You can also scarf up donated or thrown away machines to act as dumb remote terminals although those would use significant space and likely not be energy efficient. Wyse is a company who builds practically nothing but almost-dumb 'thin" terminals.

Bottom line is I would always prefer and recommend an IP-based remote terminal over USB connections.


You may find some useful info here:

I’d try setting the second usb kbd and mouse in xorg.conf, no need to create a second screen as you’d be working on the same one.

See here also:

Multi-Pointer X - Wikipedia, the free encyclopedia

There may be some restrictions due to the window manager (KDM, GDM, etc.)

Thank you for the replies and the links. This will be my weekend project. So I will come back to report how it went.