I have never heard of editing /proc/cmdline. The grub2 config file is /etc/default/grub, I believe /etc is the directory where most system config files are found..
I edit the file /etc/default/grub then run sudo update-grub2. Works for me. And has worked since the inception of grub2. No other command needed.
Maybe what is shown in /proc/cmdline is the cmdline used for current boot? Not so sure about that. But basing that on the fact that the currently booted kernel is shown by cat /proc/cmdline.
Thats is the reason why I used cat /proc/cmdline , it was a way for me to check if my change to /etc/default/grubwere saved after I updated my grub. There are two possibilites.
Those changes ware not saved
They were but, as for now those changes aren’t reflect in cat /proc/cmdline even if all those commands
sudo dmesgor journalctl -b will show the actual command line used for current boot.
Is your computer multi-boot? Are you booting from the system you are making changes to? If it is multi-boot and you are booting from another system you might need to run sudo update-grub2 on the boot system as well.
The update-grub2 command is simply a stub for running ‘grub2-mkconfig -o /boot/grub2/grub.cfg’ to generate grub2 config file. I know of no reason why someone needs to run these commands:
sudo update-grub2 should do the job. On my computer there is no grub.cfg file anywhere in /boot/efi/EFI, do not understand that. As I understand things and as things happen on a default install of OMLx grub.cfg should be in /boot not /boot/efi. And those are separate partitions, even if /boot is part of / it is on a separate partition. This is what is on my computer:
# ls /boot/efi/EFI/openmandriva
grubx64.efi
# ls /boot/efi/EFI/'OpenMandriva_Lx_[GRUB]'
grubx64.efi
It is a multi-boot with currently 5 OMLx systems. You would need to select to use either /boot/efi/EFI/openmandriva or /boot/efi/EFI/'OpenMandriva_Lx_[GRUB]' In BIOS/UEFI firmware. When the system boots it can only use one of those.
As a tester I do a lot of OMLx installs in VM’s and on hardware and I have never seen grub.cfg anywhere other than in /boot. Specifically /boot/grub2/grub.cfg. Now it is possible there are things I do not know and have not seen but I can only report of what I see here or what I can factually prove from other sources.
There are a heck of a lot of articles about this online like this and this. Note that some distros use update-grub where OMLx uses update-grub2 and /boot/grub vs. /boot/grub2 that is just a naming difference.
I found the reason for that. I didn’t think that my other system on other drive is to blame for all that mess.. I was unknowingly use grub debian instead of grub open mandriva
First I had to
sudo: Executes the command with administrative (root) privileges, required to modify the motherboard's NVRAM.
efibootmgr: The tool used to manage UEFI Boot Manager entries.
-c (--create): Directs the tool to create a new boot entry.
-d /dev/nvme0n1 (--disk): Specifies the physical disk where the EFI system partition resides (NVMe drive in this case).
-p 1 (--part): Specifies the partition number of the EFI partition on the disk (Partition 1).
-L "OpenMandriva" (--label): The text label that will be displayed in your BIOS/UEFI boot menu.
-l '\EFI\openmandriva\grub.efi' (--loader): The specific path to the EFI executable. Note: Backslashes \ are used as per the EFI specification, departing from the standard Linux forward slash.
Then re arange my sudo efibootmgr -o 0003,0006,0000 in this exact way. The 0003 parametr is my openmandriva uefi OS
Then I had to put mandriva as first boot option in uefi / bios. I have no clue why system put my sata ssd as first boot insted of my nvme.
At last after restart I go with sudo update-grub2
Reboot
Finaly I have
cat /proc/cmdline
BOOT_IMAGE=/boot/vmlinuz-6.14.2-desktop-3omv2590 root=UUID=c35f542b-c087-4ca5-9893-b422a97e12e4 ro quiet splash logo.nologo audit=0 rd.timeout=120 dm_mod.use_blk_mq=1 rd.systemd.sh
ow_status=0 systemd.show_status=0 amdgpu.dcdebugmask=0x10
The issue was aditional unnesecary grub on sda drive. This grub should not been there . All this mess As usual was user error