On Sun, Apr 11, 2010 at 10:08 AM, Michael McCallister <mike@xxxxxxxxxxxx> wrote: > I have an existing raid10,f2 array with four drives, all running on a single > SATA controller. I have a second controller to add to the system and I'd like > to split the existing drives between the two controllers. I'm hoping to make > the configuration more robust against the possibility of a single controller > failure. It would also be nice to get more performance out of the array, though > I doubt having a single controller is a bottleneck with only 4 7200RPM drives. > > So with four drives sda, sdb, sdc, and sdd and two controllers C1 and C2, should > I go with > > C1: sda, sdb > C2: sdc, sdd > > or > > C1: sda, sdc > C2: sdb, sdd > > or some other configuration? > > I've looked through the last six months of messages in the archives, and the > md(4) and mdadm(8) manpages, and the wiki on https://raid.wiki.kernel.org/ and > didn't see anything that quite answers this question at a level I can > understand. If there is a reference I can consult, I'm happy to keep digging. > > If it will help, the output of /proc/mdstat and "mdadm --detail" on the md > device are included below. > > > Mike McCallister > > > # cat /proc/mdstat > Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] > [raid10] > md3 : active raid10 sda5[0] sdd5[3] sdc5[2] sdb5[1] > 1445318656 blocks super 1.1 256K chunks 2 far-copies [4/4] [UUUU] > bitmap: 6/345 pages [24KB], 2048KB chunk > > # mdadm --detail /dev/md3 > /dev/md3: > Version : 01.01.03 > Creation Time : Sun Nov 9 22:47:00 2008 > Raid Level : raid10 > Array Size : 1445318656 (1378.36 GiB 1480.01 GB) > Used Dev Size : 1445318656 (689.18 GiB 740.00 GB) > Raid Devices : 4 > Total Devices : 4 > Preferred Minor : 3 > Persistence : Superblock is persistent > > Intent Bitmap : Internal > > Update Time : Sun Apr 11 11:47:09 2010 > State : active > Active Devices : 4 > Working Devices : 4 > Failed Devices : 0 > Spare Devices : 0 > > Layout : near=1, far=2 > Chunk Size : 256K > > Name : ozark:3 > UUID : e7705941:e81cfbe1:7bf6ab9f:2b979a89 > Events : 84 > > Number Major Minor RaidDevice State > 0 8 5 0 active sync /dev/sda5 > 1 8 21 1 active sync /dev/sdb5 > 2 8 37 2 active sync /dev/sdc5 > 3 8 53 3 active sync /dev/sdd5 > > > -- > 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 > I'd use smartctl to get the drive serial numbers, then move what are currently shown as sdb5 and sdd5 to your new controller during a coldboot. -- 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
