On Wed, Jul 15, 2015 at 5:07 AM, Austin S Hemmelgarn <ahferro...@gmail.com> wrote: > I've managed to get the other filesystems I was having issues with mounted > again with the device= options and clear_cache after running btrfs dev scan > a couple of times. It seems to me (at least from what I'm seeing) that > there is some metadata that isn't synchronized properly between the disks.
OK see if this logic follows without mistakes: The fs metadata is raid6, and therefore is broken up across all drives. Since you successfully captured an image of the file system with btrfs-image, clearly user space tool is finding a minimum of n-2 drives. If it didn't complain of missing drives, it found n drives. And yet the kernel is not finding n drives. And even with degraded it still won't mount, therefore it's not finding n-2 drives. By "drives" I mean either the physical device, or more likely whatever minimal metadata is necessary for "assembling" all devices into a volume. I don't know what that nugget of information is that's on each physical device, separate from the superblocks (which I think is distributed at logical addresses and therefore not on every physical drive), and if we have any tools to extract just that and debug it. -- Chris Murphy -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
