As I understand it the fundamental issue is primarily down to OEM
graphics drivers for older machines being incompatible with the >1903
version of Win 10.
Although I've not had the problem myself it initially seemed to me from
what I read that it's all to do with the server end and there'd be
nothing the client could do, but further reading, and from what Brett
and Andrew report, it suggests that may not be the case?
While the issue appears to be recognised, and the WDDM->XDDM change on
the server fixes it, I couldn't find anything that explicitly sorted it
from the client end using FreeRDP. Most writers suggested it was up to
M$ to fix, and patch KB4512941 was meant to deal with it, but I get the
feeling that doesn't actually sort it either.
From some further reading it seemed possible that there could also be a
link between the issue and particular VM's, but it appeared a little
tenuous.
If I could reproduce the issue I'd be happy to trial a few things at the
client end (passing some parms to FreeRDP, trialling a different
VM/distribution etc), but as I specifically block M$ 'updates' to our
client machines (and/or they're fairly new so the graphics driver issue
doesn't arise) I can't...
So to cap it off; right at this point I couldn't find anything simple
one could do with Guacamole/FreeRDP, other than perhaps flag something
more useful to the user if error 114 arose?
Therefore I think some more info/testing is needed to find a resolution
or provide a workaround at the client (Guacamole/FreeRDP) end, otherwise
I guess the issue may dissipate as machines are upgraded, or M$ provide
a [working] fix?
On 18/02/2020 12:32 a.m., Nick Couchman wrote:
On Mon, Feb 17, 2020 at 12:00 AM ivanmarcus
<[email protected]> wrote:
Brett (and Andrew),
It does seem there's some RD issues with Win10 1903 vs 1809,
although they're meant to be addressed by now.
If you've still got the 18.04 VM running with Guacamole 1.1.0 you
could try disabling "use WDDM graphics display driver for remote
desktop connection" in the Win10 machine?
This should be available via Group Policy Editor:
-Local Computer Policy
-Computer Configuration
-Administrative Templates
-Windows Components
-Remote Desktop Services
-Remote Session Environment
It could be a complete red herring, but if it were me I'd spend a
couple of minutes trying it out.
As I expect you know Guacamole 1.0.0 uses FreeRDP 1.x whereas
1.1.0 utilises the new FreeRDP 2. I believe this is still in beta;
maybe there's some issues still to be resolved and although I
didn't see any from a cursory inspection it might be worth a more
in-depth check?
Wow, nice find! I wonder if there's a flag you can/should set on the
RDP connection side to disable this, or if there's something else that
needs to be implemented in Guacamole's RDP library to either take
advantage of it or tune it down.
-Nick
