On Tue, 2014-04-01 at 18:34 +0100, nixbugz wrote: > -----Original Message----- > From: Jiang, Dave > Sent: Tuesday, April 1, 2014 5:08 PM > To: nixbugz@xxxxxxxxxxx > Cc: linux-raid@xxxxxxxxxxxxxxx ; Paszkiewicz, Artur > Subject: Re: Can't grow IMSM RAID5 > > On Tue, 2014-04-01 at 16:42 +0100, nixbugz wrote: > > Hello > > > > I’m stuck trying to add a 4th disc to an IMSM RAID5 container: > > > > # mdadm -a /dev/md127 /dev/sdb > > mdadm: added /dev/sdb > > > > # mdadm --grow --raid-devices=4 > > /dev/md127 --backup-file=/mnt/spare/raid-backup-file > > mdadm: Cannot read superblock for /dev/md127 > > I think you need to grow the RAID volume and not the container? So it > would be /dev/md0 or /dev/md1 instead of /dev/md127? Here's URL to the > Linux IMSM user's manual that hopefully may be of use: > http://www.intel.com/support/chipsets/rste/sb/CS-033622.htm > > > > > # cat /proc/mdstat > > Personalities : [raid6] [raid5] [raid4] > > md0 : active raid5 sdd[2] sda[1] sdc[0] > > 1887436800 blocks super external:/md127/0 level 5, 128k chunk, > > algorithm 0 [3/3] [UUU] > > > > md1 : active (auto-read-only) raid5 sdc[2] sdd[1] sda[0] > > 66077696 blocks super external:/md127/1 level 5, 128k chunk, > > algorithm > > 0 [3/3] [UUU] > > > > md127 : inactive sdb[3](S) sda[2](S) sdc[1](S) sdd[0](S) > > 12612 blocks super external:imsm > > > > unused devices: <none> > > > > # mdadm –V > > mdadm - v3.3 - 3rd September 2013 > > > > > > I don’t know if this is related but mdmon has trouble finding the ports: > > > > # mdadm --detail-platform -v > > mdadm: checking metadata 0.90 > > mdadm: 0.90 metadata is platform independent > > mdadm: checking metadata 1.x > > mdadm: 1.x metadata is platform independent > > mdadm: checking metadata ddf > > mdadm: ddf metadata is platform independent > > mdadm: checking metadata imsm > > mdmon: found Intel(R) SATA RAID controller at 0000:00:1f.2. > > Platform : Intel(R) Matrix Storage Manager > > Version : 11.6.0.1702 > > RAID Levels : raid0 raid1 raid10 raid5 > > Chunk Sizes : 4k 8k 16k 32k 64k 128k > > 2TB volumes : supported > > 2TB disks : supported > > Max Disks : 6 > > Max Volumes : 2 per array, 4 per controller > > I/O Controller : /sys/devices/pci0000:00/0000:00:1f.2 (SATA) > > mdmon: failed to determine port number for > > /sys/devices/pci0000:00/0000:00:1f.2/ata1/host0/target0:0:0/0:0:0:0 > > mdmon: failed to enumerate ports on SATA controller at 0000:00:1f.2. > > mdadm: checking metadata mbr > > mdadm: mbr metadata is platform independent > > mdadm: checking metadata gpt > > mdadm: gpt metadata is platform independent > > # > > Artur, any ideas why mdmon isn't happy in this instance? > > Thanks for your quick response. I wasn't sure whether to grow container or > volume but this from man mdadm decided it: > > Using GROW on containers is currently supported only for Intel's > IMSM > container format. The number of devices in a container can > be > increased - which affects all arrays in the container ... > > It gives the same message anyway when applied to the volume md0. > > This extract from the Intel doc you linked to says the same (note that md0 > is the container here :-) > > The example below adds a single disk to the RAID container and then > grows the > volume(s). Because IMSM volumes inside a container must span the same > number of disks, all volumes are expanded. > ... > mdadm –a /dev/md0 /dev/sde > mdadm –G /dev/md0 –n 4 --backup-file=/tmp/backup > > Might it be something to do with what's already on the new drive? > This is an Intel DQ77MK motherboard. Ooops my bad. It's been a while since I played with the grow feature. Even if there's something on the drive, it doesn't make sense to me why it complains not able to read the superblock on /dev/md127. And adding the drive to the container should've updated the super block on that drive I would think.... Although I wonder if the mdmon issue is a clue.... I assume all the drives are attached to the Intel AHCI controller right? Maybe Artur will have a better idea as he is much more familiar with the actual code. ��.n��������+%������w��{.n�����{����w��ܨ}���Ơz�j:+v�����w����ޙ��&�)ߡ�a����z�ޗ���ݢj��w�f
