On Fri, 2025-03-14 at 22:14 -0700, Dave Close wrote:
I received a new SanDisk "Extreme" 128 GB SD card today and used rpi- imager to put a new OS onto it. After completing successfully, I was able to mount the linux partition and make a backup copy onto a hard disk. But then...
# umount /mnt # e2fsck -c /dev/sdb2 e2fsck 1.47.1 (20-May-2024) rootfs: recovering journal Checking for bad blocks (read-only test): 0.00% done, 0:00 elapsed. (0/0/0 errdone rootfs: Updating bad block inode. Pass 1: Checking inodes, blocks, and sizes Pass 2: Checking directory structure Pass 3: Checking directory connectivity Pass 4: Checking reference counts Pass 5: Checking group summary information rootfs: ***** FILE SYSTEM WAS MODIFIED ***** rootfs: 145349/332592 files (0.1% non-contiguous), 1130966/1330176 blocks # mount /dev/sdb2 /mnt mount: /mnt: wrong fs type, bad option, bad superblock on /dev/sdb2, missing codepage or helper program, or other error. dmesg(1) may have more information after failed mount system call.
So, again, "e2fsck -c" seems to destroy the superblock. In this case, I had no suspicion of any problem with the card; I only ran e2fsck to see if the same problem would occur. It did.
I'm not directly formatting the card, rpi-imager does that, so choosing a different filesystem is not reasonable. I am confident that the card has the advertised capacity; SanDisk is not a fly-by-night vendor.
Reputable supplier for the card? (Even then, forgeries have gotten into normal supply chains, from time to time).
Failing card slot?
Failing card reader?
I would have first tried writing to the card with something other than what was used with the last problem, just to remove it from the equation.