Neil Brown said: (by the date of Fri, 3 Dec 2010 12:25:47 +1100) > > I can afford reboots, no problem here, but isn't there some simpler way? > > Yes, there is a simpler way, but no: it isn't going to work anyway. Great! Thank you for your reply, I must remember this in case when I'll want to grow a non-raid10 array :) And now: LVM to the rescue! best regards Janek Kozicki > You cannot 'grow' a RAID10 array at all - sorry. It is sufficiently complex > that it needs quite a bit of time to design, code, and test. And I haven't > had that time yet. > > But if you could resize a RAID10 array, this is what I would do: > > 1/ For each devices (sda, sdb, sdc) > - fail and remove each partition from the respective array. > - run 'kpartx -a /dev/sdX'. This will create partitions in > /dev/mapper/ with the same names. > - --re-add these partitions to the arrays. The presence of a > write-intent-bitmap will mean that resync is almost instant. > > 2/ Use fdisk to change the partition tables. > > 3/ run 'kpartx -a /dev/sdX' again on each device. This will change the > partitions even while they are active. > > 4/ For the partitions which have changed size, find the matching > /dev/md2/md/dev-dm0X/size > and > echo 0 > /dev/md2/md/dev-dm-X/size > > This will cause md to relocate the metadata to the new end of the device. > Not that these partitions (created by kpartx) are device-mapper partitions > so have names like 'dm-0' and 'dm-1'. > > 5/ mdadm -G /dev/md2 --size max > This bit unfortunately won't work. > > > NeilBrown > > > > > > > > > below is my raid layout, I need to grow md2 by few spare gigabytes > > left at the end of /dev/sd[abc]. > > > > kernel 2.6.29 (impossible to upgrade at the moment). > > > > Personalities : [raid0] [raid1] [raid10] > > md2 : active raid10 sda2[0] sdc2[2] sdb2[1] > > 185381376 blocks super 1.0 512K chunks 2 far-copies [3/3] [UUU] > > bitmap: 1/6 pages [4KB], 16384KB chunk > > > > md1 : active raid1 sdc1[2](W) sdb1[3](W) > > 9767416 blocks super 1.0 [2/2] [UU] > > bitmap: 1/150 pages [4KB], 32KB chunk > > > > md0 : active raid1 sde1[0] sdd1[2] sda1[1] > > 9767424 blocks [3/3] [UUU] > > bitmap: 1/150 pages [4KB], 32KB chunk > > > > unused devices: <none> > > atak:/home/janek# mdadm -D /dev/md2 > > /dev/md2: > > Version : 1.0 > > Creation Time : Thu Sep 2 11:47:39 2010 > > Raid Level : raid10 > > Array Size : 185381376 (176.79 GiB 189.83 GB) > > Used Dev Size : 123587584 (117.86 GiB 126.55 GB) > > Raid Devices : 3 > > Total Devices : 3 > > Persistence : Superblock is persistent > > > > Intent Bitmap : Internal > > > > Update Time : Thu Dec 2 16:41:02 2010 > > State : active > > Active Devices : 3 > > Working Devices : 3 > > Failed Devices : 0 > > Spare Devices : 0 > > > > Layout : far=2 > > Chunk Size : 512K > > > > Name : atak:2 (local to host atak) > > UUID : f2a75dbe:5ac91a1f:c09da3c0:f6f69c9c > > Events : 28 > > > > Number Major Minor RaidDevice State > > 0 8 2 0 active sync /dev/sda2 > > 1 8 18 1 active sync /dev/sdb2 > > 2 8 34 2 active sync /dev/sdc2 > > > > best regards > > -- Janek Kozicki http://janek.kozicki.pl/ | -- 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
