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Btrfs to ext4

Hi,
I’m trying to transition from btrfs to ext4. It was a native btrfs install, so no rollback. After some research, I’ve gathered that the most efficient way is to just tar everything from btrfs /(@), and extract it back into a newly formated ext4. Of course, that isn’t enough. Naturally, I also edited fstab, replacing the old / mount with the new one.
I’ve also read that its necessary to run a grub-mkconfig, and install the linux package (after chrooting). Even after doing all of that, it still wouldn’t boot. Because I restored my previous backup, I can’t remember the exact error, but it was something on the lines of “mount: unknown filesystem type ‘ext4’”. I’m running manjaro, and the drive its on has an efi partition, a root partition, and a home partition.
Can anyone tell me what I’m doing wrong, and what the proper steps are?

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its hard to tell exactly what the problem is without the exact logs of your attempts to boot.
but it sounds like your boot environment is misconfigured. can you describe your boot environment?
EFI or MBR?
do you use a bootloader? if so, which one?
do you use an initial ramdisk?
what are the boot parameters you’re using?

I haven’t messed much with the default manjaro installation. Its a GPT table, I use grub (I remember doing something to it to stop the sparse file not allowed message, can’t recall what).
I’m not sure if an initial ramdisk is being used. How can I check that? After the error message I mentioned, I was sent into a shell with an unfamiliar filesystem. I guess that was the ramdisk.

can you show us your grub boot entry?
edit the entry while in grub. i want to see that wall(s) of text.

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I will reproduce the steps above to get the system to that “broken” state, and I will share the entries when its done.

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The issue was grub related. It appears that I didn’t properly reinstall it the first time, but now its fine. Thanks for your help.

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