[SOLVED] Unable to grow a raid 5 array

horde · 09-12-2009, 06:20 PM

I have gotten past the problem of adding an extra drive to my system but now it seems I cant grow the raid to utilise all of the space available to me.

# mdadm --detail /dev/md1
/dev/md1:
Version : 0.91
Creation Time : Sat Nov 22 13:42:02 2008
Raid Level : raid5
Array Size : 2930279808 (2794.53 GiB 3000.61 GB)
Used Dev Size : 976759936 (931.51 GiB 1000.20 GB)
Raid Devices : 5
Total Devices : 5
Preferred Minor : 1
Persistence : Superblock is persistent

Update Time : Sun Sep 13 08:15:57 2009
State : clean
Active Devices : 5
Working Devices : 5
Failed Devices : 0
Spare Devices : 0

Layout : left-symmetric
Chunk Size : 128K

Delta Devices : 1, (4->5)

UUID : 0f2561a9:81e8cd4a:10e4ddb4:49a3b4a7
Events : 0.359652

Number Major Minor RaidDevice State
0 8 17 0 active sync /dev/sdb1
1 8 49 1 active sync /dev/sdd1
2 8 65 2 active sync /dev/sde1
3 8 81 3 active sync /dev/sdf1
4 8 33 4 active sync /dev/sdc1

As far as I can tell it had finished resyncing and all is ready for the next stage.

# df -k
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sda2 20641788 4368880 15224268 23% /
udev 897268 244 897024 1% /dev
/dev/sda3 284948380 20526788 249947028 8% /home
/dev/md1 2884298328 2714620256 23164084 100% /mediaData

# mdadm --grow --size max /dev/md1
mdadm: Cannot set device size/shape for /dev/md1: Device or resource busy

I read a number of posts that said bitmaps can cause this issue and to remove them but when I try I get:

# mdadm --grow -b none /dev/md1
mdadm: no bitmap found on /dev/md1

Where do I go now?

horde · 09-14-2009, 08:40 AM

OK eventually tried the following with success. Just posting here in case someone else has the same problem.

Given that all of the references said it was bitmap related and that removing a bitmap would solve the problem I decided I'd try to fix it by adding a bitmap which I would then remove - this did the trick ....

So :

mdadm --grow -b internal /dev/md1
mdadm --grow -b none /dev/md1
mdadm --grow --size max /dev/md1

and then I just needed to

e2fsck -f /dev/md1 -C 0
resize2fs /dev/md1

Hope this helps someone else