On 7/10/13 1:56 AM, "Ole Tange" <tange@xxxxxxxxxx> wrote: >I tested reshaping a raid0 on 2 devices to 4 devices. > >It seems the reshape first converted to RAID4 and then quickly >converted to RAID0. > >I have now done that on a bigger array. The only change that I am aware >of is: > >* The 2+2 devices are much larger (25 TB each compared to 1 GB each) >* The system has crashed during the reshape > >So right now the system looks like this: > >Personalities : [raid6] [raid5] [raid4] >md3 : active raid4 md1[0] md5[3] md4[4] md2[1] > 109396484096 blocks super 1.2 level 4, 512k chunk, algorithm 0 >[5/4] [UUUU_] > >which looks like the RAID4 just before the final step. > >I then tried: > ># mdadm --grow /dev/md3 -n 4 -l 0 --backup-file reshape.bak > >But that seems to cause the reshape to go through the full 100 TB again: > >root@lemaitre:/lemaitre-internal# cat /proc/mdstat >Personalities : [raid6] [raid5] [raid4] >md3 : active raid4 dm-0[0] dm-3[3] dm-2[4] dm-1[1] > 109396484096 blocks super 1.2 level 4, 512k chunk, algorithm 0 >[5/4] [UUUU_] > [>....................] reshape = 0.0% (28100/27349121024) >finish=32428.7min speed=14050K/sec > >So I cancelled that and rolled back to the situation before (this was >possible because I ran this on overlay files): > >Personalities : [raid6] [raid5] [raid4] >md3 : active raid4 md1[0] md5[3] md4[4] md2[1] > 109396484096 blocks super 1.2 level 4, 512k chunk, algorithm 0 >[5/4] [UUUU_] > >Can I convert that to RAID0? Can I do that without having to wait the >2-3 weeks a full reshape takes? > All you need to do to directly convert to RAID0 is: echo 0 > /sys/block/md3/md/level Sam -- 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
