I have two installations of OS 15.6 on two different disks.
Depending on from which installation I write the bootloader/grub, the boot screen has different resolution, although I am not aware of a difference in the installation procedure.
What difference is causing that different resolution?
(My answer could seem off-topic, and I’m sorryof not having a better answer)
Personally, I would move my second install on a virtal machine and use the 2nd disk for backups or data
You can check/change the console resolution in YaST->Bootloader->Kernel Parameters
1 Like
I’m laughing at myself, it was so evident…
YaST->Bootloader->Kernel Parameters says that it’s automatically determined by grub2.
So why it is determined in both setups in a different way?
the two installations exist for historical reasons and are not meant o be used cuncurrently.
the reason for my question is not that the different resolutions cause any problem. the reason is that I had some issues with GPUs and that I want to understand some background.
Set the console resolution on both systems to the same fixed value. Still a difference?
Compare the contents from /etc/default/grub on both systems.
they are identical (execpt for the disk UUID of course)
Check for this file (“grub”), in /etc/default sub-dir:
user@machine: /etc/default> ll
total 52
...
-rw-r--r-- 1 root root 1691 Feb 6 06:39 grub <======
-rw-r--r-- 1 root root 1681 Apr 8 2024 grub.old
-rw-r--r-- 1 root root 1371 Sep 10 2020 rmt
...
user@machine:/etc/default>
And scroll through the file, to change the parameters to your preference:
# If you change this file, run 'grub2-mkconfig -o /boot/grub2/grub.cfg' afterwards to update
# /boot/grub2/grub.cfg.
# Uncomment to set your own custom distributor. If you leave it unset or empty, the default
# policy is to determine the value from /etc/os-release
GRUB_DISTRIBUTOR=
GRUB_DEFAULT=saved
GRUB_HIDDEN_TIMEOUT=0
GRUB_HIDDEN_TIMEOUT_QUIET=true
GRUB_TIMEOUT=8
GRUB_CMDLINE_LINUX_DEFAULT="preempt=full plymouth.enable=0 splash=none mitigations=auto security=apparmor"
GRUB_CMDLINE_LINUX=""
# Uncomment to automatically save last booted menu entry in GRUB2 environment
# variable `saved_entry'
# GRUB_SAVEDEFAULT="true"
#Uncomment to enable BadRAM filtering, modify to suit your needs
# This works with Linux (no patch required) and with any kernel that obtains
# the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...)
# GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef"
#Uncomment to disable graphical terminal (grub-pc only)
GRUB_TERMINAL="gfxterm"
# The resolution used on graphical terminal
#note that you can use only modes which your graphic card supports via VBE
# you can see them in real GRUB with the command `vbeinfo'
GRUB_GFXMODE="auto"
# Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to Linux
# GRUB_DISABLE_LINUX_UUID=true
#Uncomment to disable generation of recovery mode menu entries
# GRUB_DISABLE_RECOVERY="true"
#Uncomment to get a beep at grub start
# GRUB_INIT_TUNE="480 440 1"
GRUB_BACKGROUND=
GRUB_THEME=/boot/grub2/themes/openSUSE/theme.txt
SUSE_BTRFS_SNAPSHOT_BOOTING="true"
GRUB_USE_LINUXEFI="true"
GRUB_DISABLE_OS_PROBER="false"
GRUB_ENABLE_CRYPTODISK="n"
GRUB_CMDLINE_XEN_DEFAULT="vga=gfx-1024x768x16"
Another possibile reference:
Show grub.cfg in both cases. Photo of the both different screens would be useful as well.
diff grub.cfg_highres grub.cfg_lowres
82,87c82
< set root='hd0,gpt2'
< if [ x$feature_platform_search_hint = xy ]; then
< search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt2 --hint-efi=hd0,gpt2 --hint-baremetal=ahci0,gpt2 548770d9-00f7-497a-8262-28785835449c
< else
< search --no-floppy --fs-uuid --set=root 548770d9-00f7-497a-8262-28785835449c
< fi
---
> search --no-floppy --fs-uuid --set=root 964195c4-c9f4-406a-8f29-8db06d7f96ff
112,117c107
< set root='hd0,gpt2'
< if [ x$feature_platform_search_hint = xy ]; then
< search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt2 --hint-efi=hd0,gpt2 --hint-baremetal=ahci0,gpt2 548770d9-00f7-497a-8262-28785835449c
< else
< search --no-floppy --fs-uuid --set=root 548770d9-00f7-497a-8262-28785835449c
< fi
---
> search --no-floppy --fs-uuid --set=root 964195c4-c9f4-406a-8f29-8db06d7f96ff
147c137
< menuentry 'openSUSE Leap 15.6' --class opensuse --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-548770d9-00f7-497a-8262-28785835449c' {
---
> menuentry 'openSUSE Leap 15.6' --class opensuse --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-964195c4-c9f4-406a-8f29-8db06d7f96ff' {
153,160c143,145
< set root='hd0,gpt2'
< if [ x$feature_platform_search_hint = xy ]; then
< search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt2 --hint-efi=hd0,gpt2 --hint-baremetal=ahci0,gpt2 548770d9-00f7-497a-8262-28785835449c
< else
< search --no-floppy --fs-uuid --set=root 548770d9-00f7-497a-8262-28785835449c
< fi
< echo 'Loading Linux 6.4.0-150600.23.38-default ...'
< linux /boot/vmlinuz-6.4.0-150600.23.38-default root=UUID=548770d9-00f7-497a-8262-28785835449c splash=silent resume=/dev/disk/by-uuid/b79a0059-63d7-44ae-bdf9-d5d6468923c3 preempt=full quiet security=apparmor mitigations=auto
---
> search --no-floppy --fs-uuid --set=root 964195c4-c9f4-406a-8f29-8db06d7f96ff
> echo 'Loading Linux 6.4.0-150600.23.42-default ...'
> linux /boot/vmlinuz-6.4.0-150600.23.42-default root=UUID=964195c4-c9f4-406a-8f29-8db06d7f96ff splash=silent resume=/dev/disk/by-uuid/e1b47b9b-4821-4596-9bc1-fc63a483195d preempt=full quiet security=apparmor mitigations=auto
162c147
< initrd /boot/initrd-6.4.0-150600.23.38-default
---
> initrd /boot/initrd-6.4.0-150600.23.42-default
164,165c149,174
< submenu 'Advanced options for openSUSE Leap 15.6' --hotkey=1 $menuentry_id_option 'gnulinux-advanced-548770d9-00f7-497a-8262-28785835449c' {
< menuentry 'openSUSE Leap 15.6, with Linux 6.4.0-150600.23.38-default' --hotkey=2 --class opensuse --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-6.4.0-150600.23.38-default-advanced-548770d9-00f7-497a-8262-28785835449c' {
---
> submenu 'Advanced options for openSUSE Leap 15.6' --hotkey=1 $menuentry_id_option 'gnulinux-advanced-964195c4-c9f4-406a-8f29-8db06d7f96ff' {
> menuentry 'openSUSE Leap 15.6, with Linux 6.4.0-150600.23.42-default' --hotkey=2 --class opensuse --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-6.4.0-150600.23.42-default-advanced-964195c4-c9f4-406a-8f29-8db06d7f96ff' {
> load_video
> set gfxpayload=keep
> insmod gzio
> insmod part_gpt
> insmod ext2
> search --no-floppy --fs-uuid --set=root 964195c4-c9f4-406a-8f29-8db06d7f96ff
> echo 'Loading Linux 6.4.0-150600.23.42-default ...'
> linux /boot/vmlinuz-6.4.0-150600.23.42-default root=UUID=964195c4-c9f4-406a-8f29-8db06d7f96ff splash=silent resume=/dev/disk/by-uuid/e1b47b9b-4821-4596-9bc1-fc63a483195d preempt=full quiet security=apparmor mitigations=auto
> echo 'Loading initial ramdisk ...'
> initrd /boot/initrd-6.4.0-150600.23.42-default
> }
> menuentry 'openSUSE Leap 15.6, with Linux 6.4.0-150600.23.42-default (recovery mode)' --hotkey=3 --class opensuse --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-6.4.0-150600.23.42-default-recovery-964195c4-c9f4-406a-8f29-8db06d7f96ff' {
> load_video
> set gfxpayload=keep
> insmod gzio
> insmod part_gpt
> insmod ext2
> search --no-floppy --fs-uuid --set=root 964195c4-c9f4-406a-8f29-8db06d7f96ff
> echo 'Loading Linux 6.4.0-150600.23.42-default ...'
> linux /boot/vmlinuz-6.4.0-150600.23.42-default root=UUID=964195c4-c9f4-406a-8f29-8db06d7f96ff single
> echo 'Loading initial ramdisk ...'
> initrd /boot/initrd-6.4.0-150600.23.42-default
> }
> menuentry 'openSUSE Leap 15.6, with Linux 6.4.0-150600.23.38-default' --class opensuse --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-6.4.0-150600.23.38-default-advanced-964195c4-c9f4-406a-8f29-8db06d7f96ff' {
171,176c180
< set root='hd0,gpt2'
< if [ x$feature_platform_search_hint = xy ]; then
< search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt2 --hint-efi=hd0,gpt2 --hint-baremetal=ahci0,gpt2 548770d9-00f7-497a-8262-28785835449c
< else
< search --no-floppy --fs-uuid --set=root 548770d9-00f7-497a-8262-28785835449c
< fi
---
> search --no-floppy --fs-uuid --set=root 964195c4-c9f4-406a-8f29-8db06d7f96ff
178c182
< linux /boot/vmlinuz-6.4.0-150600.23.38-default root=UUID=548770d9-00f7-497a-8262-28785835449c splash=silent resume=/dev/disk/by-uuid/b79a0059-63d7-44ae-bdf9-d5d6468923c3 preempt=full quiet security=apparmor mitigations=auto
---
> linux /boot/vmlinuz-6.4.0-150600.23.38-default root=UUID=964195c4-c9f4-406a-8f29-8db06d7f96ff splash=silent resume=/dev/disk/by-uuid/e1b47b9b-4821-4596-9bc1-fc63a483195d preempt=full quiet security=apparmor mitigations=auto
182c186
< menuentry 'openSUSE Leap 15.6, with Linux 6.4.0-150600.23.38-default (recovery mode)' --hotkey=3 --class opensuse --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-6.4.0-150600.23.38-default-recovery-548770d9-00f7-497a-8262-28785835449c' {
---
> menuentry 'openSUSE Leap 15.6, with Linux 6.4.0-150600.23.38-default (recovery mode)' --hotkey=1 --class opensuse --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-6.4.0-150600.23.38-default-recovery-964195c4-c9f4-406a-8f29-8db06d7f96ff' {
188,193c192
< set root='hd0,gpt2'
< if [ x$feature_platform_search_hint = xy ]; then
< search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt2 --hint-efi=hd0,gpt2 --hint-baremetal=ahci0,gpt2 548770d9-00f7-497a-8262-28785835449c
< else
< search --no-floppy --fs-uuid --set=root 548770d9-00f7-497a-8262-28785835449c
< fi
---
> search --no-floppy --fs-uuid --set=root 964195c4-c9f4-406a-8f29-8db06d7f96ff
195c194
< linux /boot/vmlinuz-6.4.0-150600.23.38-default root=UUID=548770d9-00f7-497a-8262-28785835449c single
---
> linux /boot/vmlinuz-6.4.0-150600.23.38-default root=UUID=964195c4-c9f4-406a-8f29-8db06d7f96ff single
198a198,221
> menuentry 'openSUSE Leap 15.6, with Linux 6.4.0-150600.21-default' --class opensuse --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-6.4.0-150600.21-default-advanced-964195c4-c9f4-406a-8f29-8db06d7f96ff' {
> load_video
> set gfxpayload=keep
> insmod gzio
> insmod part_gpt
> insmod ext2
> search --no-floppy --fs-uuid --set=root 964195c4-c9f4-406a-8f29-8db06d7f96ff
> echo 'Loading Linux 6.4.0-150600.21-default ...'
> linux /boot/vmlinuz-6.4.0-150600.21-default root=UUID=964195c4-c9f4-406a-8f29-8db06d7f96ff splash=silent resume=/dev/disk/by-uuid/e1b47b9b-4821-4596-9bc1-fc63a483195d preempt=full quiet security=apparmor mitigations=auto
> echo 'Loading initial ramdisk ...'
> initrd /boot/initrd-6.4.0-150600.21-default
> }
> menuentry 'openSUSE Leap 15.6, with Linux 6.4.0-150600.21-default (recovery mode)' --hotkey=1 --class opensuse --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-6.4.0-150600.21-default-recovery-964195c4-c9f4-406a-8f29-8db06d7f96ff' {
> load_video
> set gfxpayload=keep
> insmod gzio
> insmod part_gpt
> insmod ext2
> search --no-floppy --fs-uuid --set=root 964195c4-c9f4-406a-8f29-8db06d7f96ff
> echo 'Loading Linux 6.4.0-150600.21-default ...'
> linux /boot/vmlinuz-6.4.0-150600.21-default root=UUID=964195c4-c9f4-406a-8f29-8db06d7f96ff single
> echo 'Loading initial ramdisk ...'
> initrd /boot/initrd-6.4.0-150600.21-default
> }
217c240
< menuentry 'Windows Boot Manager (on /dev/nvme0n1p1)' --class windows --class os $menuentry_id_option 'osprober-efi-1AF0-12B1' {
---
> menuentry 'Windows Boot Manager (on /dev/nvme1n1p1)' --class windows --class os $menuentry_id_option 'osprober-efi-1AF0-12B1' {
the computer is a laptop with two GPU.
I wonder whether the behavior depends on whether the builtin GPU or the nvidia is selected.
I guess that it makes no difference before you log in, because sddm or gdm, etc. .do tell the system which GPU it has to use. Be careful, my souvenirs are old and may be wrong. Please tell me if it’s the case.
Anyway, always verify what people tell you to do on your beloved computer.
If, in the installation with the high resolution boot screen, I select in BIOS to use the nvidia GPU instead of “dynamic” then it results as well in the low resolution boot screen.
Slightly confusing output of the cfg’s
Might check back in my previous post for a hint, especially the documentation page.
GRUB_GFXMODE=auto
Set that to an explicit resolution on both cfg files.
It’s very possible “auto” results in different interpretations for each booter.
I don’t want to end up with a unbootable system.
can I test the resolution from with grub during boot?
I checked the available resolutions with videoinfo, and I can set gfxmode=…
but how can I apply it to see the result?
YAST -Bootloader should tell /change the resolution.
There is videotest (and vbetest on PC BIOS) command, but it may be missing from the EFI signed image. You never mentioned whether you are using EFI or legacy BIOS.
I’m using EFI
Are both systems configured for the Secure Boot support?
grep -Ev '^(#|$)' /etc/sysconfig/bootloader
efibootmgr -v
And explain what is what in the efibootmgr output.
Yes
SECURE_BOOT="yes"
TRUSTED_BOOT="no"
UPDATE_NVRAM="yes"
BootCurrent: 0001
Timeout: 0 seconds
BootOrder: 0001,0004,0000,2002,2001,2003
Boot0000* openSUSE HD(1,GPT,d5e8788c-93a7-4c90-8f84-b0af50ed0542,0x800,0x100000)/File(\EFI\opensuse\grubx64.efi)RC
Boot0001* opensuse-secureboot HD(1,GPT,d5e8788c-93a7-4c90-8f84-b0af50ed0542,0x800,0x100000)/File(\EFI\opensuse\shim.efi)
Boot0002* EFI PXE 0 for IPv4 (88-A4-C2-E3-69-48) PciRoot(0x0)/Pci(0x1d,0x6)/Pci(0x0,0x0)/MAC(88a4c2e36948,0)/IPv4(0.0.0.00.0.0.0,0,0)RC
Boot0003* EFI PXE 0 for IPv6 (88-A4-C2-E3-69-48) PciRoot(0x0)/Pci(0x1d,0x6)/Pci(0x0,0x0)/MAC(88a4c2e36948,0)/IPv6([::]:<->[::]:,0,0)RC
Boot0004* Windows Boot Manager HD(1,GPT,b5eff67d-47df-4535-9bb1-3d017eca96e5,0x800,0x82000)/File(\EFI\Microsoft\Boot\bootmgfw.efi)WINDOWS.........x...B.C.D.O.B.J.E.C.T.=.{.9.d.e.a.8.6.2.c.-.5.c.d.d.-.4.e.7.0.-.a.c.c.1.-.f.3.2.b.3.4.4.d.4.7.9.5.}...e................
Boot2001* EFI USB Device RC
Boot2002* EFI DVD/CDROM RC
Boot2003* EFI Network RC