Hi people,

This problem doesn't seem to duplicate other threads, as there's no "grub-rescue" option. Perhaps I'll need to provide more details, but it went like this (LFS-SysV 11.2):

(lfs chroot) root:/sources# grub-install /dev/sda
Installing for i386-pc platform.
grub-install: error: unknown filesystem

I'd run df -h and confirmed /dev/sda1 was mounted at /boot (it's ext4)

The GPT partitions are:
/dev/sda1 212M /boot ext4
/dev/sda2 1M bios_boot
/dev/sda3 16G swap
/dev/sda4 40G /root ext4

The machine is a ThinkPad X200, host dist is ArchLinux.

I've left the machine untouched at that point. Can anyone suggest how I can rescue 3 days careful work ?!

Thanks anyhow.

Is /dev/ mounted on the client ( in the chroot )?

This may be the problem: https://askubuntu.com/questions/8956...own-filesystem

Thanks to Keith Hedger fo your reply. Yes, when I did df -h, dev is mounted on /dev.

(lfs chroot) root:/sources/Linux-5.19.23 df -h
/dev/sda4 ... /
/dev/sda1 ... /boot
dev ... /dev
tmpfs ... /run

I note that I am still in the Linux-5.19.23 directory, from compiling the kernel. Might this be a mistake? NB. I changed down to /sources before running the grub-install command.

And thanks to colorpurple21859 for you response. I will chase that link, which looks 'not-dissimilar' to some other posts in Ubuntu forums I investigated, but without the 'grub-rescue' element. I used cfdisk to partition, not gparted.

I will try the "tune2fs -O ^metadata_csum_seed /dev/sda1" solution, and see what happens.

A thought: I have previously made a successful LFS-11.2 install on the X200, but on that occasion used an msdos partition table. Truth is I'm not knowledgeable enough to know whether that's relevant.

I don't have the 'update-grub' facility installed on my ArchLinux worker. But I'll try grub-probe too.

update-grub is equivalent to:
grub-mkconfig -o /boot/grub/grub.cfg

The tips from the Ubuntu forum haven't taken me anywhere. Here are the results:

(lfs chroot) root:/sources# tune2fs -l /dev/sda1 | grep metadata_csum_seed
Filesystem features: has_journal ext_attr resize_inode dir_index FEATURE_C12 filetype needs_recovery extent 64bit flex_bg metadata_csum_seed sparse_super large_file huge_file dir_nlink extra_isize metadata_csum FEATURE_R16

I'm afraid I can't deduce anything from that output.

(lfs chroot) root:/sources# grub-probe --target=fs --device /dev/sda1
grub-probe: error: unknown filesystem.
(lfs chroot) root:/sources# tune2fs -O ^metadata_csum_seed /dev/sda1
tune2fs 1.46.5 (30-Dec-2021)
tune2fs: Filesystem has unsupported read-only feature(s) while trying to open /dev/sda1
Couldn't find valid filesystem superblock.

Perhaps I might try a 'pacman -S grub-install'

Thanks colorpurple21859, I ran that familiar command, and got this:

(lfs chroot) root:/sources# grub-mkconfig -o /boot/grub/grub.cfg
Generating grub configuration file ...
Found linux image: /boot/vmlinuz-5.19.2-lfs-11.2
/usr/sbin/grub-probe: error: unknown filesystem.
Warning: os-prober will not be executed to detect other bootable partitions.
Systems on them will not be added to the GRUB boot configuration.
Check GRUB_DISABLE_OS_PROBER documentation entry.
done

So ... I'll press ahead, complete the configuration and see if she boots. Thanks for your help, and we'll see if I get to put a SOLVED sticker on this thread.

All seemed to go well in completing the installation, but sadly, it won't boot. Grub says

error: unknown filesystem
Press any key ...

I wonder just what filesystem could be such a surprise. Perhaps I'll stick with the (older) install that did work, albeit with issues. I'll post questions about them separately.

Thanks to all. Sorry I can't clean up the thread. I'll click 'solved' if requested, even if it will be a bit of a fib.

Perhaps I'll just add that the X200 in question is one of those Ministry Of Freedom machines, and there are a lot of systems it won't boot! Most recently I tried OpenBSD, FreeBSD -- all to no avail.

Anyway, thanks for the responses and advice. Maybe my skillset isn't up to fully benefiting.

Don Pedro

Sda4 may be the problem or need a newer version of tune2fs or newer version of grub.

That command has to be run on an *unmounted* filesystem to remove the feature and enable grub to recognize the filesystem (back in the day i remember it was XFS that was always having this problem of new features not being recognized by grub).

I don't know if new grub (2.12 in current LFS) supports ext4 filesystems with "metadata_csum_seed" -- I would guess yes.

Update: I confirmed on my own system grub 2.12 supports the new ext4 default filesystem layout.

Thanks bryan_S

Archlinux, my host system, as a rolling release is updated and runs grub 2:2.12-1, with e2fsprogs 1.47.0-1 so I can't get newer than those.

However I note LFS-11.2 is using grub-2.06, as is the latest LFS-12. Surely I'm still running from the Host System at the stage I described? Pray do pardon my confusion if that becomes necessary.

I'm currently having another go at building 11.2, but on an msdos partition table this time. My previous (mostly successful) installation was so based.

Why are you building 11.2 instead of 12.0? lfs 12.0 still has grub-2.06, However has the E2fsprogs-1.47.0 which would allow you to be able to disable the "metadata_csum_seed" feature. I don't think changing partition table type will help. You probably will have the same problem again. For 11.2 would suggest to bump E2fsprogs to 1.47 and/or grub to 2.12

I ran into roadblocks with 12 -- consistent (i.e. repeatable) FAILS, I forget where. Even the prolific 'Kernotex' came unstuck during his 'live' (i.e. non-edited) run at LFS-12. I simply reverted to an msdos PT of 11.2 because that's how I started the 'successful' installation I have -- partially successful, that is. Yes, perhaps it'll be no different, but SOMETHING I did must have been different.

I wish I had, at the start, kept better notes. Worklogs. But I'm often out of my depth with this stuff, and just thought to plunge in and 'give it a go'. I've had a complex experience, with two machines: Thinkpads X200 and X230i -- 11.2 and 11.3 respectively, each installation being machine specific/exclusive.

I'll report back