Known issues
Issues
Cerberos is not starting
Rocky Linux 8 + NVIDIA
Failure Recovery & Maintenance Manual
This document covers reliable recovery and maintenance of NVIDIA GPUs on Rocky Linux 8 / RHEL 8-derived systems, specifically for cases where:
- The GUI fails to start
/dev/driis missingnouveaureports "unknown chipset"- NVIDIA breaks after kernel updates
- RPM Fusion package names appear inconsistent
This manual is based on real-world recovery and reflects correct EL8 behavior.
1. Core Facts (Memorize These)
Hardware & Drivers
- Some NVIDIA GPUs are not supported by
nouveau - Message:
nouveau: unknown chipset nouveauwill never work on this hardware
Graphics Stack
- GUI requires DRM
- DRM creates
/dev/dri - On unsupported NVIDIA GPUs:
- Only the proprietary NVIDIA driver provides DRM
Kernel Rules (Critical)
- NVIDIA kernel modules must exactly match the running kernel
- Even minor version differences break the driver
- EL8 repositories do not keep old kernel graphics modules forever
2. Golden Rules
Disable Secure Boot (mandatory for NVIDIA)
Boot into multi-user.target for repairs
Pick one kernel and stay on it
Use akmod-nvidia, not dkms
Rebuild NVIDIA only for the current kernel
Do not rely on nouveau on unsupported GPUs
Do not chase old kernels
Do not mix kernels and drivers
Do not install random NVIDIA package names from blogs
3. Emergency: Boot Into Text Mode
From GRUB, edit the boot entry and append: systemd.unit=multi-user.target
After login, lock it in:
sudo systemctl set-default multi-user.target
4. Verify Secure Boot (Mandatory)
mokutil --sb-state # verify secure boot state
Must show: SecureBoot disabled
If enabled, disable Secure Boot in BIOS. There is no workaround.
5. Clean NVIDIA Reinstall (Minimal & Correct)
Step 1 - Install a Supported Kernel Stack
sudo dnf install -y \
kernel \
kernel-core \
kernel-modules \
kernel-modules-extra
sudo reboot
After reboot:
uname -r
This kernel is now your only supported kernel.
Step 2 - Enable Required Repositories
sudo dnf config-manager --set-enabled powertools
sudo dnf install -y \
https://download1.rpmfusion.org/free/el/rpmfusion-free-release-8.noarch.rpm \
https://download1.rpmfusion.org/nonfree/el/rpmfusion-nonfree-release-8.noarch.rpm
sudo dnf clean all
sudo dnf makecache
Step 3 - Install NVIDIA (Correct Package)
sudo dnf install -y akmod-nvidia
Do not manually install:
xorg-x11-drv-nvidianvidia-driver*-cuda
RPM Fusion resolves the correct userspace automatically on EL8.
Step 4 - Build NVIDIA for This Kernel Only
sudo akmods --force --kernel $(uname -r)
ls /var/cache/akmods/nvidia/ # verify
Expected: kmod-nvidia-<kernel>.rpm
Step 5 - Install the Built Module Explicitly
sudo dnf install -y /var/cache/akmods/nvidia/kmod-nvidia-*.rpm
sudo modprobe nvidia # load driver
lsmod | grep nvidia # verify
Expected:
nvidia
nvidia_drm
nvidia_modeset
nvidia_uvm
6. Validate Graphics Stack
ls /dev/dri
Expected:
card0
renderD128
Optional verification:
command -v nvidia-smi
nvidia-smi
(Probably not going to work, but that is fine. GUI works even without nvidia-smi, but it is a good confirmation.)
7. Start the GUI
sudo systemctl set-default graphical.target
sudo systemctl start graphical.target
You should now get:
- Graphical login
- Proper resolution
- Hardware acceleration
8. Make the Fix Permanent
Disable nouveau forever.
sudo nano /etc/default/grub
Set GRUB_CMDLINE_LINUX="rhgb quiet module_blacklist=nouveau"
Rebuild:
sudo grub2-mkconfig -o /boot/grub2/grub.cfg
sudo dracut --force
Pin the working kernel:
sudo grub2-set-default 0
sudo grub2-editenv list
9. Quick Diagnostic Table
| Symptom | Meaning | Fix |
|---|---|---|
/dev/dri missing |
No DRM | Fix kernel / NVIDIA |
nouveau: unknown chipset |
Unsupported GPU | Use NVIDIA |
modprobe nvidia: key not available |
Secure Boot enabled | Disable Secure Boot (SB) |
| GUI fails, text works | Driver mismatch | Rebuild NVIDIA |
| akmods builds wrong kernel | Kernel drift | Pin kernel |
10. Final Takeaway
On Rocky Linux 8, NVIDIA stability depends on kernel discipline. One kernel, one NVIDIA build, Secure Boot off, and the system is stable.
11. Additional possiblilities
Disable Wayland (recommended on your system)
Edit GDM configuration:
sudo nano /etc/gdm/custom.conf
Set:
[daemon]
WaylandEnable=false
Save, then restart GDM or reboot:
sudo systemctl restart gdm