Hi Karel, On 01/08/2013 07:01 PM, Karel Zak wrote: > On Sun, Jan 06, 2013 at 07:28:55PM +0100, Goffredo Baroncelli wrote: >> If the first superblock is valid except that the "magic field" is zeroed, >> btrfs skips the check of the other superblocks. >> If the first superblock is fully invalid, btrfs checks for the other >> superblock. > > Hmm... why inconsistent (or missing) superblock is not reported as a > problem? If I good understand the filesystem is still mountable, > right? It should, however my tests were unsuccessful :-(... Chris ? > >> So zeroing the first superblock "magic field" at the beginning seems >> that the filesystem is wiped. > > Well, this is exactly the idea behind wipefs(8), just wipe minimal > number of bytes from the device to make the filesystem invisible for > libblkid (udev, ...). This concept is relatively safe, if you make a > mistake than you can restore the magic string, your data should not > be affected by wipefs(8). I fully agree. However wipefs should zero all three superblock > > Karel > -- gpg @keyserver.linux.it: Goffredo Baroncelli (kreijackATinwind.it> Key fingerprint BBF5 1610 0B64 DAC6 5F7D 17B2 0EDA 9B37 8B82 E0B5 -- To unsubscribe from this list: send the line "unsubscribe util-linux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
