4.4.2 - Downgrade options? CRASHES Master and Clients, No Demo


  • We'll have a look at the demo issue and try to resolve it in 4.5.3. Veyon 4.5 comes with a rewritten implementation demo feature so it's likely there are still some bugs due to the big changes.


  • @tobydox

    OK!! I finally have a new clue!

    EDIT: Sometimes! I wrote the following...but then signed into two more clients, and now NOTHING is working again, not even on the one I had tested and resolve the following. ARGH!!!!

    What I THOUGHT was progress...
    If I select "All screens", Demo works, but only shows Display2). The problem is I don't really want Display 2 to go to the Clients. Display 3 is what is going to the TV monitors in the room (via HDMI splitter) and I would really like for what they see on the screen to be the same as what I display to the entire class.

    Also, Clients only receive some of my Display to their monitor...resolution differences...but this anomaly has been with Veyon for 3 years...so this is to be expected.

    If I select Screen 1 [\.\Display2], it works. No difference as above as to the amount that goes to the clients.

    If I select Screen 2 [\.\Display3], Demo does NOT work. Just sits there hanging o n "Connecting". Black screen on client until I stop Demo.

    If I select Screen 3 [\.\Display4], Demo does not work...same as above.

    I don't even know what Display 4 is as i have three Display using Built-in Video on VGA, Display Port and HDMI out all working together for 3 monitors.

    But, this work before on 4.3, just stopped working on 4.4.2. A version after 4.4.2, maybe 4.5?, brought in the option to select a screen/display. That version didn't work for crashing, nor Demo. Maybe right before you all added the option to select the screen, the coding was added that broke the Demo. ??? (just spit balling there).

    So, 4.5.2 is stable. And I have now determined that some of the options in Demo work.

    Demo options Veyon.JPG
    display settings with 3 monitors.JPG


  • Thanks for figuring out! So it seems to be related to a non-standard arrangement of screens. I'll test this and if necessary provide a bugfix 🙂


  • @drewloker

    My understanding is \\.\DISPLAY2, \\.\DISPLAY3 and \\.\DISPLAY4 are device names representing display output or screens.

    In Clone mode screens and monitors could pair as;

    \\.\DISPLAY1\Monitor0
    \\.\DISPLAY1\Monitor1

    where one screen is applied to two logical monitor devices.

    In Extended mode screens and monitors could pair as;

    \\.\DISPLAY1\Monitor0
    \\.\DISPLAY2\Monitor0

    where two screens are applied to one logical monitor device.

    You can think of \\.\DISPLAY1 and \\.\DISPLAY2 as the output of the graphics card drivers/interface (screens) while \\.\DISPLAY1\Monitor0 and \\.\DISPLAY1\Monitor1 represent the attached monitors.

    Two Nirsoft utilities, ControlMyMonitor and MultiMonitorTool, provide screen, monitor and adapter information with both GUI and command line control.

    https://www.nirsoft.net/utils/multi_monitor_tool.html

    https://www.nirsoft.net/utils/controlmymonitor.zip

    https://www.nirsoft.net/utils/multimonitortool-x64.zip

    Extract both using the 7-Zip utility, https://www.7-zip.org/download.html, and for convenience place the extracted files into the C:\Windows folder.

    Command line:
    C:\Windows\MultiMonitorTool.exe /stext "C:\Users\Public\Desktop\monitorinfo.txt"

    C:\Windows\ControlMyMonitor.exe /smonitors "C:\Users\Public\Desktop\monitorinfo2.txt"

    Question: Do any of the three monitors have touchscreens?


  • I’m not familiar with Veyon throughput or whether this is configurable. Generally I haven’t experienced performance issues using either Fullscreen demo or Window demo and though deselecting unused computers would achieve a modest performance gain my experience has been this doesn’t work very well on the fly. Since you are down to two lists I think it would be best to exit and restart Veyon whenever your selections change.


  • @DrewLoker the screen arrangement issue should be fixed in 4.5.3 - can you please test this version?


  • @tobydox

    Ok, testing now. Installing on Master.

    EDIT: Initially, it appears to be working...but no students in the room and I only logged in to one computer. But getting excited!!!

    Does this need to be deployed to all clients urgently?

    Thanks!


  • @tobydox
    Well, it worked for a second on the one computer...but then client crashed...and did not work again. It came up with the "Establishing connection..." msg, but would not establish.

    When the next class came in, the computers were locked up and had to be rebooted. 25 of the 26 computers are still on 4.5.2. So, only the one client and the master are at 4.5.3. I am not sure I want to install across the entire unless you think it will help.

    Will it make any difference if I install across the entire lab?


  • @drewloker There are some mitigations for cases where the demo server crashes in 4.5.4 (it will get restarted instantly automatically) so I strongly recommend to deploy 4.5.4 in favor of previous releases.


  • @tobydox
    Demo still doesn't work.

    I brought the whole lab up to 4.5.4.0

    It went to Demo, showed my screen for a few second on a couple of the 7 students logged in a lab of 26 clients. Then, Demo stopped working even on the couple that did get my screen.

    I was able to back out of Demo mode with out crashing their computer.

    😞


  • @drewloker said in 4.4.2 - Downgrade options? CRASHES Master and Clients, No Demo:

    Demo still doesn't work.
    I brought the whole lab up to 4.5.4.0
    It went to Demo, showed my screen for a few second on a couple of the 7 students logged in a lab of 26 clients. Then, Demo stopped working even on the couple that did get my screen.
    I was able to back out of Demo mode with out crashing their computer.

    Hello
    i have the same problem .. i opened a new topic: https://veyon.nodebb.com/topic/1258/veyon-4-5-4-vnc-serveur-crash-on-demo-mode
    where I put the logs to see if tobydox manages to understand what is wrong ...
    Fred