restarting raid arrays with uuid

Hi All

I'm not entirely sure this is rescuable. This is an old system that was kept on for scratch storage space, unfortunately it was discovered some data hadn't moved out of this area. The arrays disappeared after taking them offline and rebooting the machine.

I've checked /etc/mdadm.conf
And mdadm --examine across all of the disks
I've assembled from uuid
Ran /proc/mdstat

Any suggestions as to what to try next?

Thanks

Bryan

[root@igmimager dev]# cat /etc/mdadm.conf
ARRAY /dev/md0 metadata=1.2 name=igmimager.ncl.ac.uk:129 UUID=1dc7f560:edbfe144:0531da73:f239c583
ARRAY /dev/md1 metadata=1.2 name=inscribe_data1 UUID=2b00561d:25e97d49:65d13ea0:63aba0b7
ARRAY /dev/md2 metadata=1.2 name=igmimager.ncl.ac.uk:128 UUID=3aee46d0:ced811c7:287c9e2e:c9fcb98d
ARRAY /dev/md3 metadata=1.2 name=inscribe_data5 UUID=4108db00:e338d0eb:64f1c8c0:7c5dd4d2
ARRAY /dev/md4 metadata=1.2 name=igmimager.ncl.ac.uk:0 UUID=bc69e915:891c1a98:083d6b8d:8d99151f
ARRAY /dev/md5 metadata=1.2 name=inscribe_data4 UUID=f83ae16b:c7cf278a:199a0085:d8f68936
[root@igmimager dev]#

[root@igmimager etc]# mdadm --assemble /dev/md0 --uuid 1dc7f560:edbfe144:0531da73:f239c583
[root@igmimager etc]# mdadm --assemble /dev/md1 --uuid 2b00561d:25e97d49:65d13ea0:63aba0b7
[root@igmimager etc]# mdadm --assemble /dev/md2 --uuid 3aee46d0:ced811c7:287c9e2e:c9fcb98d
[root@igmimager etc]# mdadm --assemble /dev/md3 --uuid 4108db00:e338d0eb:64f1c8c0:7c5dd4d2
[root@igmimager etc]# mdadm --assemble /dev/md4 --uuid bc69e915:891c1a98:083d8f68936
mdadm: Bad uuid: bc69e915:891c1a98:083d8f68936
[root@igmimager etc]# mdadm --assemble /dev/md4 --uuid bc69e915:891c1a98:083d6b8d:8d99151f
mdadm: Found some drive for an array that is already active: /dev/md4
mdadm: giving up.
[root@igmimager etc]# mdadm --assemble /dev/md5 --uuid f83ae16b:c7cf278a:199a0085:d8f68936
[root@igmimager etc]# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4]
md3 : active raid5 sdi1[0] sdl1[4] sdk1[2] sdj1[1]
      5860142592 blocks super 1.2 level 5, 512k chunk, algorithm 2 [4/4] [UUUU]
      bitmap: 0/15 pages [0KB], 65536KB chunk

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-----Original Message-----
From: <redacted> [mailto:linux-raid-
owner@vger.kernel.org] On Behalf Of Bryan Hepworth
Sent: 06 June 2016 19:55
To: <redacted>
Subject: restarting raid arrays with uuid

Hi All

I'm not entirely sure this is rescuable. This is an old system that was kept on
for scratch storage space, unfortunately it was discovered some data hadn't
moved out of this area. The arrays disappeared after taking them offline and
rebooting the machine.

I've checked /etc/mdadm.conf
And mdadm --examine across all of the disks
I've assembled from uuid
Ran /proc/mdstat

Any suggestions as to what to try next?

After carefully looking at the arrays I have two back as they should be.

I've also discovered that one of the drives with gpt has a partition in it with ext4 data. Gparted has given me the device uuid which I can see in /dev/disk/by-uuid

Unfortunately it says no superblock information when I run mdadm --examine /dev/disk/by-uuid/<uuid number>

gparted  does say ext4 is clean and it does have a --raid tag so my next question is is it safe to mount this drive, or is it best to dd it elsewhere to see what's on it?

Thanks

Bryan