RAID-5 gone. Help needed.

Hi
I had to re-install the operating system, and now the raid is gone.

I have three 3 TB disks installed:
Device Start End Sectors Size Type
/dev/sdb1 40 1060289 1060250 517.7M Microsoft basic data
/dev/sdb2 1060296 2120579 1060284 517.7M Microsoft basic data
/dev/sdb3 2120584 5859515969 5857395386 2.7T Microsoft basic data
/dev/sdb4 5859515976 5860511999 996024 486.3M Microsoft basic data
All three have the same layout.

So, since I don't know how they have been configured, I was reading the larger partitions...
root@debian:/dev/md# mdadm --examine /dev/sd*3
/dev/sdb3:
Magic : a92b4efc
Version : 1.0
Feature Map : 0x0
Array UUID : 533870d3:d528464c:c7a3f292:e4606f3f
Name : 0
Creation Time : Fri Oct 13 18:01:58 2017
Raid Level : raid5
Raid Devices : 3

Avail Dev Size : 5857395112 (2793.02 GiB 2998.99 GB)
Array Size : 5857395072 (5586.05 GiB 5997.97 GB)
Used Dev Size : 5857395072 (2793.02 GiB 2998.99 GB)
Super Offset : 5857395368 sectors
Unused Space : before=0 sectors, after=296 sectors
State : clean
Device UUID : 3b9ead1c:3e64dbb0:8caa1744:60a9e6d7

Update Time : Thu Jan 31 23:19:16 2019
Checksum : 51a830c7 - correct
Events : 238945

Layout : left-symmetric
Chunk Size : 64K

Device Role : Active device 1
Array State : .AA ('A' == active, '.' == missing, 'R' == replacing)
/dev/sdc3:
Magic : a92b4efc
Version : 1.0
Feature Map : 0x0
Array UUID : 533870d3:d528464c:c7a3f292:e4606f3f
Name : 0
Creation Time : Fri Oct 13 18:01:58 2017
Raid Level : raid5
Raid Devices : 3

Avail Dev Size : 5857395112 (2793.02 GiB 2998.99 GB)
Array Size : 5857395072 (5586.05 GiB 5997.97 GB)
Used Dev Size : 5857395072 (2793.02 GiB 2998.99 GB)
Super Offset : 5857395368 sectors
Unused Space : before=0 sectors, after=296 sectors
State : clean
Device UUID : 3b9ead1c:3e64dbb0:8caa1744:60a9e6d7

Update Time : Thu Jan 31 23:19:16 2019
Checksum : 51a830c7 - correct
Events : 238945

Layout : left-symmetric
Chunk Size : 64K

Device Role : Active device 1
Array State : .AA ('A' == active, '.' == missing, 'R' == replacing)
mdadm: No md superblock detected on /dev/sdd3.

My guess is that the /dev/sdd failed and was no longer part of the raid-5 before.

root@debian:~# cat /proc/mdstat
Personalities : [raid1] [linear] [multipath] [raid0] [raid6] [raid5] [raid4] [raid10]
md124 : inactive sdb3[1](S)
2928697556 blocks super 1.0

md125 : inactive sdd1[0](S) sdc1[6](S) sdb1[5](S)
1590336 blocks super 1.0

md126 : active raid1 sdd2[4](S) sdc2[2] sdb2[0]
530128 blocks super 1.0 [2/2] [UU]

md127 : inactive sdd4[1](S) sdc4[3](S) sdb4[2](S)
1493760 blocks

unused devices: <none>

Do you have any idea on how I can proceed rebuilding the raid without loosing the data?
Thanks for any help.

Regards,
Gunnar

Statistics: Posted by groetschel — 2025-01-27 19:36 — Replies 1 — Views 39

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