Rocky 9.2 - enable BTRFS support in kernel

I am on 9.2 and I am trying to read a filesystem pulled from an encrypted SSD that was running Linux. The decryption was apparently successful but then I get an error:

“error mounting [mount point] at [name of SSD]. Filesystem type btrfs not configured in kernel”

How do I configure my kernel to read btrfs filesystems? The btrfs documentation seems to presume the kernel supports it already. Is it a module? Do I patch my kernel? grepping through the available modules already on disk has not turned up anything so far. Any pointers are appreciated.

btrfs is not a supported file system in Rocky Linux, so you will not be able to use it via normal means.

You would need to try to use the kmod sig repositories from CentOS (we don’t have the repo package available, you can get it here) or the elrepo kernel-ml/kernel-lt packages to try to get support (note that btrfs-progs does not exist in elrepo as of this writing).

To be clear, I have no desire or need for anything btrfs related as such, once I offload the data I want.

Pragmatically speaking, what happens when I upgrade to a new version of Rocky Linux? will the kernel-ml with btrfs support be superseded? What am I losing by not using the official kernel for the distro?

btrfs-progs is available here.

Non-distro kernels are not supported by Rocky. But as soon as you get the data out of that device, you can go back to the official kernel.

Is there any info how to patch the existing kernel for BTRFS?
Second choice , Is there any kernel modules for BTRFS support?

I believe using elrepo repositories will give you a kernel that has btrfs support. No need to compile your own.

1 Like

BTRFS is enabled in elrepo’s kernel-ml, but not in kernel-lt.

1 Like