Re: [HELP] open_ctree failed when mounting RAID1

Lucas Rückert
2022-06-02T14:33:22Z

On 02.06.22 2:49 PM, Jussi Kansanen wrote:
> On 5/31/22 22:50, Lucas Rückert wrote:
>> Hi,
>>
>> i run two HHD's(sda;sdb) in RAID1.
>>
>> Kernel: 4.9
>>
>> Distro: Linux odroid 4.9.277-83 #1 SMP PREEMPT Mon Feb 28 15:16:26 UTC
>> 2022 aarch64 aarch64 aarch64 GNU/Linux
>>
>> btrfs-progs: 5.4.1
>>
>> I created the filesystem with:
>>
>> mkfs.btrfs -d raid1 -m raid1 -L somelable -f /dev/sda /dev/sdb
>>
>>
>> And added it to my fstab:
>>
>> UUID=<uuid>        /mnt/somefolder     btrfs compress=zstd   0       2
>>
>>
>> When running:
>>
>> mount -a
>>
>> i get an error:
>>
>> mount: /mnt/backup: wrong fs type, bad option, bad superblock on
>> /dev/sda, missing codepage or helper program, or other error.
>>
>>
>> and dmesg reports:
>>
>> BTRFS error (device sdb): open_ctree failed
>>
>>
>>
>> Yours sincerely
>>
>> Lucas
>>
>
> Hi Lucas,
>
> Invalid mount options can be reported as "BTRFS error (device sdb):
> open_ctree failed". The reason for the error is that your kernel version
> doesn't support zstd. 4.14 kernel added support for zstd or 5.1 if you
> want to set zstd compression levels by mount option.
>
> -Jussi Kansanen

Thanks Jussi this fixed it.

Lucas