Chris Murphy posted on Mon, 28 Dec 2015 17:10:14 -0700 as excerpted: > Hi, > > I (intentionally) used wipefs -a on a device with a btrfs. As expected > btrfs check doesn't recognize the device as having a btrfs volume > anymore. > > Slightly surprising that it doesn't mention other intact supers are > found. > > Most surprising that options -s1 --repair doesn't fix it. > > I thought maybe it's intentional, only with explicitly bad magic, and > I'd get different results if it were zero'd. So I zero'd it and I get > the same results. s0 superblock isn't repaired with --repair. > > Bug? > > Of course I can fix it with echo+dd.
Btrfs check's -s option simply lets you use a different superblock. I don't believe check is designed to actually fix superblocks, tho I guess with --repair it fixes certain bad fields in them. What you want to actually recover bad superblocks from good copies is btrfs rescue super-recover. -- Duncan - List replies preferred. No HTML msgs. "Every nonfree program has a lord, a master -- and if you use the program, he is your master." Richard Stallman -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
