Thanks Barry,

On 22/7/25 18:16, Barry Scott wrote:

On 22 Jul 2025, at 04:23, fed...@eyal.emu.id.au wrote:

f42 x86_64 with all updates, i915 built in video

I have a problem where when I disconnect a monitor (e.g. using a KVM) and 
reconnect, the screen remains blank.

I checked the situation and running 'xrandr --listmonitors' shows the monitor 
is initially disconnected and then connected.
So Xorg thinks all is well, but I get no video (maybe an intel x11-server 
issue?).

Does it work if you use Wayland desktop?

I never tried it and would not take the risk right now.

I can switch to text (e.g. tty2) which works fine (is visible), but when 
switching back to tty1 the screen is blank.

Running 'xrandr --output HDMI1 --mode 3840x2160_24.00' revives the video. 
However it should run from a graphics session
(an xterm window on :0 on tty1 in my case).

Can I, somehow, issue this command from a text VT? For example start 'xterm' on 
tty1 (from tty2)?

Try like this:

XAUTHORITY=/run/user/1000/xauth_icQwML DISPLAY=:0.0 xterm

I do not have any (my uid is 500)
        /run/user/500/xauth_*

'locate' knows of none either.

I found that I can issue
        xterm -display :0
to start xterm on tty1.

However, trying
        xterm -display :0 -e xrandr --output HDMI1 --mode 3840x2160
or
        xterm -display :0 -e xrandr --display :0 --output HDMI1 --mode 3840x2160
or even
        xterm -hold -display :0 -e xrandr --display :0 --output HDMI1 --mode 
3840x2160
does not restore the video.

What does work is running (from tty2)
        xterm -display :0
then switching to tty1 (blank screen)
then typing (blind) the xrandr command. For ease I created ~/xx.sh to do the 
xrandr and it works.

So I am half way there...

It seems that unless I have tty1(Xorg) active the xrandr does not do it, but 
running the same command while on tty1 does work.

Regards,
        Eyal

You will need to figure out what the XAUTHORITY file path is each time Xorg is 
started.

Barry



TIA

--
Eyal at Home (fed...@eyal.emu.id.au)

--
Eyal at Home (fed...@eyal.emu.id.au)
--
_______________________________________________
users mailing list -- users@lists.fedoraproject.org
To unsubscribe send an email to users-le...@lists.fedoraproject.org
Fedora Code of Conduct: 
https://docs.fedoraproject.org/en-US/project/code-of-conduct/
List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines
List Archives: 
https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org
Do not reply to spam, report it: 
https://pagure.io/fedora-infrastructure/new_issue

Reply via email to