cgsecurity.org

many thanks!
I think you meant the second partition, so I ran (on the disk copy):

dd if=/dev/sdb2 of=/dev/sdc2 bs=1024 count=1 skip=1 seek=1

then, the rootfs partition was displayed in the file explorer.

then ran fsck:

sudo fsck.ext4 -f /dev/sdc2

it complained about errors I didn't have ...

ok...
it seems to me that all the superblock duplicates are all the same..

how about I try and copy the superblock of the clean card onto the defective one?

What would be the command to write a superblock back into a disk please?

hello, thanks!

here are the hexdumps for the corrupted disk:

at 1024 offset:

ubuntu@ubuntu:~$ sudo xxd -s 1024 -l 1024 /dev/sdc2
00000400: 0000 0000 0000 0000 0000 0000 0000 0000 ................
00000410: 0000 0000 0000 0000 0000 0000 0000 0000 ................
00000420: 0000 0000 0000 0000 ...

hello,

here the hexdump for the corrupted card:

00008000: 0880 0000 0880 0100 0880 0200 0880 0300 ................
00008010: 0880 0400 0880 0c00 0880 0d00 0880 1800 ................
00008020: 0880 2800 0880 3e00 0880 7900 0880 ab00 ..(...>...y.....
00008030: 0000 0000 0000 0000 0000 0000 0000 ...

ok, I found another post with a similar message from fsck.ext4, so it looks like the standard output for this type of error.

thanks for the link to https://linux.die.net/man/8/fsck.ext4.

I listed the expected superblocks suggested by the page with the mke2fs command:

ubuntu@ubuntu:~/Documents ...

hello,

thanks a lot for the clues! Was able to ddrescue the card and it completed without reading bad sectors.

fsck returns:

fsck.ext4: Bad magic number in super-block while trying to open /dev/sdc2
/dev/sdc2:
The superblock could not be read or does not describe a valid ext2/ext3/ext4 ...

hello,


First of all, thanks a lot for this forum and for any clue that could be provided as I'm all new to this utility and kind of issues.

The issue is on a raspberry disk which was created by the raspberry imager on a microSD card.
It used to display two main partitions:
bootfs
rootfs

The ...