On 15/04/10 02:04, Neil Brown wrote: > On Wed, 14 Apr 2010 23:10:06 +0100 > James Braid <jamesb@xxxxxxxxxxxx> wrote: >> # cat /proc/mdstat >> Personalities : [raid6] [raid5] [raid4] >> md4 : active raid6 sde[0] sdg[5](S) sdh[6](S) sdc[3] sdd[2] sdf[1] >> 4395415488 blocks level 6, 64k chunk, algorithm 18 [5/4] [UUUU_] > > So it has converted your RAID5 to RAID6 with a special layout which places > all the Q blocks on the one disk. That disk is missing. So your data is > still safe, but the layout is somewhat unorthodox, and it didn't grow to 6 > devices like you asked it to. Yeah, I was a a bit confused as to why that didn't work. >> After the grow failed, I stopped the array and restarted it. At that >> point it appears to be continuing with the grow process? Is this correct? > ... >> # cat /proc/mdstat >> Personalities : [raid6] [raid5] [raid4] >> md4 : active raid6 sde[0] sdh[5] sdg[6](S) sdc[3] sdd[2] sdf[1] >> 4395415488 blocks level 6, 64k chunk, algorithm 18 [5/4] [UUUU_] >> [>....................] recovery = 0.0% (147712/1465138496) >> finish=661.1min speed=36928K/sec > > What is happening here is that the spare (sdh) is getting the Q blocks > written to it. When this completes you will have full 2-disk redundancy but > the layout will not be optimal and the array wont be any bigger. > To fix this you would: > > mdadm --grow --backup-file=/root/backup.md4 --raid-devices=6 \ > --layout=normalise /dev/md4 > > Hopefully this will not hit the same problem that you hit before. This seems to be working OK - thanks Neil! The man pages cover this quite well too. -- 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
