We have several Rocky 9.x machines in our lab running 24/7 and it happens from time to time that the video output stops working. It then helps to restart the display-manager, but this is a bit sub-optimal solution. Does someone has similar experience and have a solution? I never find something in /var/log/messages that indicates a problem for me, but maybe I just don’t see it or look at the wrong place.
Look for errors with journalctl.
user@rocky: ~$ sudo journalctl --unit=display-manager.service --priority=warning
Once you have found the time the crush occured you can post the messages of all priorities here:
user@rocky: ~$ sudo journalctl --unit=display-manager.service --since="2012-10-30 18:17:16" --until="2012-10-30 18:19:16"
Thanks, on one machine that is currently affected I get
-- No entries --
So not helpful :(, but I think that the problem might be somewhere else and that restarting the display manager just cures the symptom and not the disease. I could imagine that it is some sort of power-saving feature.
Maybe you can find with journcalct any warnings and errors related to your issue, not specifically from the very unit.
Things which might be relevant are
/usr/libexec/gdm-x-session[2841]: (--) NVIDIA(GPU-0): DFP-1: disconnected
/usr/libexec/gdm-x-session[2841]: (--) NVIDIA(GPU-0): DFP-1: Internal DisplayPort
/usr/libexec/gdm-x-session[2841]: (--) NVIDIA(GPU-0): DFP-1: 2670.0 MHz maximum pixel clock
/usr/libexec/gdm-x-session[2841]: (--) NVIDIA(GPU-0):
/usr/libexec/gdm-x-session[2841]: (--) NVIDIA(GPU-0): DFP-3: disconnected
/usr/libexec/gdm-x-session[2841]: (--) NVIDIA(GPU-0): DFP-3: Internal DisplayPort
/usr/libexec/gdm-x-session[2841]: (--) NVIDIA(GPU-0): DFP-3: 2670.0 MHz maximum pixel clock
/usr/libexec/gdm-x-session[2841]: (--) NVIDIA(GPU-0):
/usr/libexec/gdm-x-session[2841]: (--) NVIDIA(GPU-0): DELL U2723QE (DFP-3): connected
/usr/libexec/gdm-x-session[2841]: (--) NVIDIA(GPU-0): DELL U2723QE (DFP-3): Internal DisplayPort
/usr/libexec/gdm-x-session[2841]: (--) NVIDIA(GPU-0): DELL U2723QE (DFP-3): 2670.0 MHz maximum pixel clock
/usr/libexec/gdm-x-session[2841]: (--) NVIDIA(GPU-0):
and/or
systemd-udevd[873]: nvidia: Process '/usr/bin/bash -c '/usr/bin/mknod -Z -m 666 /dev/nvidiactl c $(grep nvidia-frontend /proc/devices | cut -d \ -f 1) 255'' failed with exit code 1.
systemd-udevd[864]: nvidia: Process '/usr/bin/bash -c '/usr/bin/mknod -Z -m 666 /dev/nvidiactl c $(grep nvidia-frontend /proc/devices | cut -d \ -f 1) 255'' failed with exit code 1.
systemd-udevd[873]: nvidia: Process '/usr/bin/bash -c 'for i in $(cat /proc/driver/nvidia/gpus/*/information | grep Minor | cut -d \ -f 4); do /usr/bin/mknod -Z -m 666 /dev/nvidia${>
systemd-udevd[864]: nvidia: Process '/usr/bin/bash -c 'for i in $(cat /proc/driver/nvidia/gpus/*/information | grep Minor | cut -d \ -f 4); do /usr/bin/mknod -Z -m 666 /dev/nvidia${>
kernel: nvidia_uvm: module uses symbols from proprietary module nvidia, inheriting taint.
systemd-udevd[873]: nvidia_modeset: Process '/usr/bin/bash -c '/usr/bin/mknod -Z -m 666 /dev/nvidia-modeset c $(grep nvidia-frontend /proc/devices | cut -d \ -f 1) 254'' failed with>
which appeared before. The last one I don’t really get, but it is related to the nvidia driver and thus potentially the output.
Please may I ask, how do you restart the display-manager?
Thank you kindly.
Dear ashwiz I restart it as
sudo systemctl restart display-manager
Do you have a suggestion for the cause of my problem?
No sorry, I have the same problem.
No problem, I hope that maybe someone else can point me to a more sustainable solution. My I ask if you are using an nvidia card? We assume that it is related to our nvidia cards. Do you use gnome or KDE?