Re: raid5 grow problem

[Justin Piszcz <jpiszcz@xxxxxxxxxxxxxxx>]

Adding XFS mailing list to this e-mail to show that the grow for xfs 
worked.

On Thu, 17 Aug 2006, ÊæÐÇ wrote:

> > I've only tried growing a RAID5, which was the only RAID that I remember
> > being supported (to grow) in the kernel, I am not sure if its posible to
> i know this,but how you grow your raid5,what's your mdadm version?
> need anyother configure before creat md & use mdadm -G ..to grow?
> > grow other types of RAID arrays.
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0) Compile your kernel with experimental raid5 re-sizing support.
1) Add a spare to the RAID5.
2) Grow the array.

Like this:

p34:~# mdadm --create /dev/md3 /dev/hda1 /dev/hde1 /dev/sdc1 --level=5 
--raid-disks=3
mdadm: array /dev/md3 started.
p34:~# mdadm -D /dev/md3
/dev/md3:
        Version : 00.90.03
  Creation Time : Fri Jul  7 15:44:24 2006
     Raid Level : raid5
     Array Size : 781417472 (745.22 GiB 800.17 GB)
    Device Size : 390708736 (372.61 GiB 400.09 GB)
   Raid Devices : 3
  Total Devices : 3
Preferred Minor : 3
    Persistence : Superblock is persistent

    Update Time : Fri Jul  7 15:44:24 2006
          State : clean, degraded, recovering
 Active Devices : 2
Working Devices : 3
 Failed Devices : 0
  Spare Devices : 1

         Layout : left-symmetric
     Chunk Size : 64K

 Rebuild Status : 0% complete

           UUID : cf7a7488:64c04921:b8dfe47c:6c785fa1
         Events : 0.1

    Number   Major   Minor   RaidDevice State
       0       3        1        0      active sync   /dev/hda1
       1      33        1        1      active sync   /dev/hde1
       3       8       33        2      spare rebuilding   /dev/sdc1
p34:~#

p34:~# df -h | grep /raid5
/dev/md3              746G   80M  746G   1% /raid5
p34:~# umount /dev/md3
p34:~# mdadm -D /dev/md3
/dev/md3:
        Version : 00.90.03
  Creation Time : Fri Jul  7 15:44:24 2006
     Raid Level : raid5
     Array Size : 781417472 (745.22 GiB 800.17 GB)
    Device Size : 390708736 (372.61 GiB 400.09 GB)
   Raid Devices : 3
  Total Devices : 4
Preferred Minor : 3
    Persistence : Superblock is persistent

    Update Time : Fri Jul  7 18:25:29 2006
          State : clean
 Active Devices : 3
Working Devices : 4
 Failed Devices : 0
  Spare Devices : 1

         Layout : left-symmetric
     Chunk Size : 64K

           UUID : cf7a7488:64c04921:b8dfe47c:6c785fa1
         Events : 0.26

    Number   Major   Minor   RaidDevice State
       0       3        1        0      active sync   /dev/hda1
       1      33        1        1      active sync   /dev/hde1
       2       8       33        2      active sync   /dev/sdc1

       3      22        1        -      spare   /dev/hdc1

p34:~# mdadm /dev/md3 --grow --raid-disks=4
mdadm: Need to backup 384K of critical section..
mdadm: ... critical section passed.
p34:~# cat /proc/mdstat
Personalities : [raid1] [raid5] [raid4]
md1 : active raid1 sdb2[1] sda2[0]
      136448 blocks [2/2] [UU]

md2 : active raid1 sdb3[1] sda3[0]
      70268224 blocks [2/2] [UU]

md3 : active raid5 hdc1[3] sdc1[2] hde1[1] hda1[0]
      781417472 blocks super 0.91 level 5, 64k chunk, algorithm 2 [4/4] 
[UUUU]
      [>....................]  reshape =  0.0% (85120/390708736) 
finish=840.5min speed=7738K/sec

md0 : active raid1 sdb1[1] sda1[0]
      2200768 blocks [2/2] [UU]

unused devices: <none>
p34:~# cat /proc/mdstat
Personalities : [raid1] [raid5] [raid4]
md1 : active raid1 sdb2[1] sda2[0]
      136448 blocks [2/2] [UU]

md2 : active raid1 sdb3[1] sda3[0]
      70268224 blocks [2/2] [UU]

md3 : active raid5 hdc1[3] sdc1[2] hde1[1] hda1[0]
      781417472 blocks super 0.91 level 5, 64k chunk, algorithm 2 [4/4] 
[UUUU]
      [>....................]  reshape =  0.0% (286284/390708736) 
finish=779.8min speed=8342K/sec

md0 : active raid1 sdb1[1] sda1[0]
      2200768 blocks [2/2] [UU]

unused devices: <none>
p34:~#

p34:~# mount /raid5

p34:~# xfs_growfs /raid5
meta-data=/dev/md3               isize=256    agcount=32, agsize=6104816 
blks
         =                       sectsz=4096  attr=0
data     =                       bsize=4096   blocks=195354112, imaxpct=25
         =                       sunit=16     swidth=48 blks, unwritten=1
naming   =version 2              bsize=4096
log      =internal               bsize=4096   blocks=32768, version=2
         =                       sectsz=4096  sunit=1 blks
realtime =none                   extsz=196608 blocks=0, rtextents=0
data blocks changed from 195354112 to 195354368
p34:~#

p34:~# umount /raid5

p34:~# mount /raid5
p34:~# df -h
/dev/md3              746G   80M  746G   1% /raid5
p34:~#