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GRUB not finding 2nd instance of Fedora for multi-boot

I have two separate instances of Fedora 40 installed (Xfce and KDE) on a drive with several partitions. The reason why is, it's a low-spec laptop, and I wanted to minimize any additional "fluff" on each installation. I was trying not to have multiple DEs installed on the same OS installation.

Xfce was installed first, and worked great. Then I altered the partition sizes, created new ones and installed the KDE spin of F40.

Now, there are no GRUB entries for the Xfce spin--only three for KDE (latest and previous kernel + recovery).

I've tried running os-prober, which does find the Xfce version:

Code:

$ sudo os-prober 

/dev/sda3:Fedora Linux 40 (Xfce):Fedora:linux:btrfs:UUID=a5807fe9-f2f6-42b3-b8a2-e0b7ea03bdf0:subvol=root00

Then...

Code:

$ sudo grub2-mkconfig -o /boot/efi/EFI/fedora/grub.cfg

Generating grub configuration file ...

Found Fedora Linux 40 (Xfce) on /dev/sda3

Adding boot menu entry for UEFI Firmware Settings ...

done

However when I run the following:

Code:

$ sudo cat /boot/efi/EFI/fedora/grub.cfg

grub.cfg does not show the Xfce in the os-prober section:

Code:

### BEGIN /etc/grub.d/30_os-prober ###



### END /etc/grub.d/30_os-prober ###

If I have to give up one or the other, I'd rather have access to the Xfce installation. It "just worked" and the KDE installation is shaky at best on this low-powered laptop. The KDE installation was installed just to see how it would perform, whereas the Xfce installation was set up to my liking.

What am I doing wrong here?

Thanks in advance...

Have you tried running update grub?

Quote:

Originally Posted by frankbell (Post 6500618)

Have you tried running update grub?

"update-grub" does not exist in Fedora.

The article you linked lists:

Code:

sudo grub-mkconfig -o /boot/grub/grub.cfg

Which is the Fedora version of "update-grub"

Code:

$ sudo grub2-mkconfig -o /boot/efi/EFI/fedora/grub.cfg

I'm getting the same result, either way...

set GRUB_ENABLE_BLSCFG=false in /etc/default/grub and rerun grub2-mkconfig

Quote:

Originally Posted by colorpurple21859 (Post 6500623)

set GRUB_ENABLE_BLSCFG=false in /etc/default/grub and rerun grub2-mkconfig

That did...something.

Code:

$ sudo grub2-mkconfig -o /boot/efi/EFI/fedora/grub.cfg

Now showed this:

Code:

Generating grub configuration file ...

Found linux image: /boot/vmlinuz-6.8.8-300.fc40.x86_64

Found initrd image: /boot/initramfs-6.8.8-300.fc40.x86_64.img

fgrep: warning: fgrep is obsolescent; using grep -F

Found linux image: /boot/vmlinuz-6.8.5-301.fc40.x86_64

Found initrd image: /boot/initramfs-6.8.5-301.fc40.x86_64.img

fgrep: warning: fgrep is obsolescent; using grep -F

Found linux image: /boot/vmlinuz-0-rescue-a07923d2c524436688708621f98c6e90

Found initrd image: /boot/initramfs-0-rescue-a07923d2c524436688708621f98c6e90.img

fgrep: warning: fgrep is obsolescent; using grep -F

Found Fedora Linux 40 (Xfce) on /dev/sda3

Adding boot menu entry for UEFI Firmware Settings ...

done

It found the Xfce installation...

Booting now looks a bit different. My GRUB options are Fedora, Advanced options and UEFI. Advanced Options lists the same two kernels and a recovery, but all three entries now have a separate recovery option.

But still no Xfce option. :scratch:

have this in /etc/default/grub, and rerun grub2-mkconfig

Code:

GRUB_DISABLE_OS_PROBER=false

Quote:

Originally Posted by colorpurple21859 (Post 6500658)

have this in /etc/default/grub, and rerun grub2-mkconfig

Code:

GRUB_DISABLE_OS_PROBER=false

Done... I am still not sure which grub.cfg file is being used by GRUB, so I've been building both /boot/grub2/grub.cfg and /boot/efi/EFI/fedora/grub.cfg

I've always run os-prober beforehand. When I run 'cat' on either file and examine the contents, the Xfce option isn't listed.

Code:

$ sudo grep menuentry /boot/grub2/grub.cfg

yields

Code:

menuentry 'Fedora' --class fedora --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-simple-c20285c1-ed0d-4e74-992e-1f703981f455' {

submenu 'Advanced options for Fedora' $menuentry_id_option 'gnulinux-advanced-c20285c1-ed0d-4e74-992e-1f703981f455' {

        menuentry 'Fedora Linux (6.8.8-300.fc40.x86_64) 40 (KDE Plasma)' --class fedora --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-6.8.8-300.fc40.x86_64-advanced-c20285c1-ed0d-4e74-992e-1f703981f455' {

        menuentry 'Fedora Linux (6.8.8-300.fc40.x86_64) 40 (KDE Plasma) (recovery mode)' --class fedora --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-6.8.8-300.fc40.x86_64-recovery-c20285c1-ed0d-4e74-992e-1f703981f455' {

        menuentry 'Fedora Linux (6.8.5-301.fc40.x86_64) 40 (KDE Plasma)' --class fedora --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-6.8.5-301.fc40.x86_64-advanced-c20285c1-ed0d-4e74-992e-1f703981f455' {

        menuentry 'Fedora Linux (6.8.5-301.fc40.x86_64) 40 (KDE Plasma) (recovery mode)' --class fedora --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-6.8.5-301.fc40.x86_64-recovery-c20285c1-ed0d-4e74-992e-1f703981f455' {

        menuentry 'Fedora Linux (0-rescue-a07923d2c524436688708621f98c6e90) 40 (KDE Plasma)' --class fedora --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-0-rescue-a07923d2c524436688708621f98c6e90-advanced-c20285c1-ed0d-4e74-992e-1f703981f455' {

        menuentry 'Fedora Linux (0-rescue-a07923d2c524436688708621f98c6e90) 40 (KDE Plasma) (recovery mode)' --class fedora --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-0-rescue-a07923d2c524436688708621f98c6e90-recovery-c20285c1-ed0d-4e74-992e-1f703981f455' {

        menuentry 'UEFI Firmware Settings' $menuentry_id_option 'uefi-firmware' {

Edit: It may be of interest to note that in the UEFI boot menu, there are two Fedora options, and both boot to KDE. No other options are available.

Was the installation of the XFCE version of Fedora an EFI install? If it was a Legacy install and is on the same drive it probably won't boot from an EFI Grub.

What happens when you run: sudo grub2-mkconfig /boot/grub2/grub.cfg
The grub.cfg file generally used on most Linux systems with this command is the one in the /boot/grub2 directory and the grub.cfg file on the EFI partition generally points to this main grub.cfg file which contains the menuentries. You might take a look at the link below to the FedoraProject. I don't use Fedora so don't know what changes they make to Grub.

https://fedoraproject.org/wiki/GRUB_2

Assuming /dev/sda2 is the boot partition for the xfce fedora add this to /etc/grub.d/40_custom:

Code:

menuentry 'fedora xfce' {

set root=(hd0,2)

configfile /grub2/grub.cfg

}

The other changes you made to /etc/default/grub can be reverted if you so desire.
rerun grub2-mkconfig

Quote:

Originally Posted by colorpurple21859 (Post 6500807)

Assuming /dev/sda2 is the boot partition for the xfce fedora add this to /etc/grub.d/40_custom:

Code:

menuentry 'fedora xfce' {

set root=(hd0,2)

configfile /grub2/grub.cfg

}

The other changes you made to /etc/default/grub can be reverted if you so desire.
rerun grub2-mkconfig

This worked! I chose the Xfce option and it then went to a sub menu listing the installed kernel versions as well as a recovery option.

I'm just curious as to why the Xfce wouldn't appear otherwise.

Grub has problems picking up other distros kernels that have a btrfs file system. I think it has something to do with how the files are organized on a btrfs partition. The sub menu listing is the grub.cfg of the other installed fedora system.

Quote:

Originally Posted by colorpurple21859 (Post 6501005)

Oddly, while booted into Xfce, The Xfce options do not exist when I look at Grub in grub customizer...

Quote:

Oddly, while booted into Xfce, The Xfce options do not exist when I look at Grub in grub customize

I think that is because fedora uses something called BLSCFG where grub references config files in /boot/loader/entries to produce grub default menu entries

before running grub-customizer so grub-customizer will pick up the other fedora mount it with a command similar to this:

Code:

mount /dev/sda3 -t btrfs -o subvol=root00,compress=zstd /mnt

will need to edit the entry and add this as a kernel option

Code:

rootflags=subvol=root00

change root00 if needed to match the root subvolume and sda3 to match the system partition you are attempting to add a grub menu.