On 2017-11-14 07:48, Roman Mamedov wrote:
On Tue, 14 Nov 2017 10:36:22 +0200
Klaus Agnoletti <klaus@xxxxxxxxxxxx> wrote:
Obviously, I want /dev/sdd emptied and deleted from the raid.
* Unmount the RAID0 FS
* copy the bad drive using `dd_rescue`[1] into a file on the 6TB drive
(noting how much of it is actually unreadable -- chances are it's mostly
intact)
* physically remove the bad drive (have a powerdown or reboot for this to be
sure Btrfs didn't remember it somewhere)
* set up a loop device from the dd_rescue'd 2TB file
* run `btrfs device scan`
* mount the RAID0 filesystem
* run the delete command on the loop device, it will not encounter I/O
errors anymore.
While the above procedure will work, it is worth noting that you may
still lose data.
[1] Note that "ddrescue" and "dd_rescue" are two different programs for the
same purpose, one may work better than the other. I don't remember which. :)
As a general rule, GNU ddrescue is more user friendly for block-level
copies, while Kurt Garlof's dd_rescue tends to be better for copying at
the file level. Both work fine in terms of reliability though.
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
