[yonatan]

Please don't say "URGENT", for me its urgent if you need to call an ambulance..

it's all about mdadm , either man mdadm or get a professional to help you with this,
remember the rules for data protection as said in some classes

disk drives / raid configure = don't know , no go!

Make sure you got your mdadm.conf file set correctly with the right raid UUID, also make sure all members are live and kicking with fd set as the partition type.
don't assemble a live disk.
also if possible, don't run it live - umount, fsck , rebuild ,mount

[zimsters]

Have you tried google mdadm?
Use rescue mode, remove the failed disk from the array, add the new drive, resync.

i've tried that - added new drive. it correctly shows 3 drives in my array all of which are active and appear ok but it's marked inactive. how do i get it to rebuild / resync it all?

[3r1c]

Have you tried google mdadm?
Use rescue mode, remove the failed disk from the array, add the new drive, resync.

[zimsters]

hey guys,

so ovh intervened to replace one of my failed drives which made up one of my raid 5 elements.

upon reboot I see:


md3 : inactive sda[0] sdd3[3] sdb3[1]
2887223168 blocks


My entire filesystem is gone at the moment. I need to get that raid drive back up, any ideas?

some more info:

#mdadm --assemble --scan
mdadm: No arrays found in config file or automatically

mdadm --detail /dev/md3
/dev/md3:
Version : 00.90
Creation Time : Tue Aug 24 18:34:47 2010
Raid Level : raid5
Used Dev Size : 955230336 (910.98 GiB 978.16 GB)
Raid Devices : 4
Total Devices : 3
Preferred Minor : 3
Persistence : Superblock is persistent

Update Time : Sat Feb 18 11:10:21 2012
State : active, degraded, Not Started
Active Devices : 3
Working Devices : 3
Failed Devices : 0
Spare Devices : 0

Layout : left-symmetric
Chunk Size : 64K

UUID : 577a0e5a:1226cbdd:a4d2adc2:26fd5302
Events : 0.26443801

Number Major Minor RaidDevice State
0 8 0 0 active sync /dev/sda
1 8 19 1 active sync /dev/sdb3
2 0 0 2 removed
3 8 51 3 active sync /dev/sdd3

mdadm /dev/md3 --assemble -u 577a0e5a:1226cbdd:a4d2adc2:26fd5302
mdadm: device /dev/md3 already active - cannot assemble it