On Sun, Mar 31, 2019 at 11:48 PM Glenn Trigg <ggtr...@gmail.com> wrote: > > Hi Chris, > > After booting the fedora usb stick (running rc2), I got the same results. > > On Mon, 1 Apr 2019 at 08:35, Chris Murphy <li...@colorremedies.com> wrote: > > > > On Sat, Mar 30, 2019 at 5:43 PM Glenn Trigg <ggtr...@gmail.com> wrote: > ... > > > > I'm confused because "can't read superblock" isn't found in fs/btrfs. > > I'm only finding it in fs/gfs2/ops_fstype.c > > > > From what you provided, /dev/sda1 definitely has a valid btrfs > > superblock. I wonder if there's some other stale something or other on > > this partition? > > > > What do you get for > > > > $ sudo blkid > > /dev/sda1: LABEL="data" UUID="d5e50511-3e31-4de6-ba37-c5841895be9f" > UUID_SUB="a28b0f34-f14d-492b-995b-2dd8a78ec9bb" TYPE="btrfs" > PARTUUID="efa240ec-01" > /dev/sdc1: LABEL="data" UUID="d5e50511-3e31-4de6-ba37-c5841895be9f" > UUID_SUB="d9c56d7a-21a1-4197-a701-5493392e1ae1" TYPE="btrfs" > PARTUUID="1aae1443-c03e-4509-ad06-124a64c4df4f" > > > $ sudo wipefs -an /dev/sda1 /dev/sdc1 > > /dev/sda1: 8 bytes were erased at offset 0x00010040 (btrfs): 5f 42 48 > 52 66 53 5f 4d > /dev/sdc1: 8 bytes were erased at offset 0x00010040 (btrfs): 5f 42 48 > 52 66 53 5f 4d > > > $ sudo mount -v -o ro,nologreplay,usebackuproot > > mount: /data: can't read superblock on /dev/sda1. >
That is the sort of error I'd expect if the device were in fstab to be mounted at /data. But you're running this mount command while booted from the Fedora USB stick? I'm pretty lost at this point. Anyway, your best bet is to scrape with `btrfs restore` and then move on, i.e. start over with a new file system. Right now I have no confidence in the repair tools, but maybe a developer will come along and offer some different advice on additional steps. For sure any of the user space repair options are a last resort. There should be a btrfs-progs 5.0 soon that is supposed to be safer, and might be worth a shot. But I think it's a coin toss. -- Chris Murphy
