> -----Original Message----- > From: linux-raid-owner@xxxxxxxxxxxxxxx [mailto:linux-raid-owner@xxxxxxxxxxxxxxx] On Behalf Of NeilBrown > Sent: Wednesday, May 11, 2011 1:32 AM > To: Peter Kovari > Cc: linux-raid@xxxxxxxxxxxxxxx > Subject: Re: RAID5 -> RAID6 conversion, please help > You have a RAID6 array in a non-standard config where there Q block (the > second parity block) is always on the last device rather than rotated around > the various devices. > The array is simply recovering that 6th drive to the spare. > When it finished you will have a perfectly functional RAID6 array with full > redundancy. It might perform slightly differently to a standard layout - > I've never performed any measurements to see how differently. > If you want to (after the recovery completes) you could convert to a regular > RAID6 with > mdadm -G /dev/md0 --layout=normalise --backup=/some/file/on/a/different/device > but you probably don't have to. Thank you Neil, this explains everything. I suppose the layout difference mostly affects - if affects - write performance. Since this is a media server, with mostly read operations, I probably will leave it as it is. > The old meta on sdd will not have been a problem. > What version of mdadm did you use to try to start the reshape? $ lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 10.04.2 LTS Release: 10.04 Codename: lucid $ mdadm --version mdadm - v3.1.4 - 31st August 2010 $ uname -a Linux FileStation 2.6.34-020634-generic #020634 SMP Mon May 17 19:27:49 UTC 2010 x86_64 GNU/Linux Cheers, Peter -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
