Maybe look at testdisk/photorec to attempt to scrape any recoverable file data.
]]>$ sudo dd bs=4M if=isofoo.iso of=/dev/sdc
483+1 Datensätze ein
483+1 Datensätze aus
2028060672 bytes (2,0 GB, 1,9 GiB) copied, 16,89 s, 120 MB/s
So, shit.
$ sudo btrfs check --repair /dev/sdc
enabling repair mode
No valid Btrfs found on /dev/sdc
Couldn't open file system
$ sudo btrfs-find-root /dev/sdc
No valid Btrfs found on /dev/sdc
ERROR: open ctree failed
OK, the btrfs wiki says there is a second superblock at 64 MiB (overwritten too in my case) and a third at 256 GiB ("0x4000000000"). But how to restore it? And how to restore the general btrfs frame metathings? Would be glad for any help!
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