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D-Link Network Storage => DNS-340L => Topic started by: circlecomputers on December 10, 2017, 04:23:09 AM

Title: DNS340L appears to have forgotten raid-5 config
Post by: circlecomputers on December 10, 2017, 04:23:09 AM
Hi

I'm hoping this is  simple fix, we had a power cut and when the NAs came back on it appears to have forgotton the TAID-5 volume accreoss the 4 drives.

My experience of RAID-5 comes from server implementaions where the config is normally stored in multiple locations, on the controller and and also in on the drive set so I was surprised that the NAS didn't recover automatically.

The situation is that the drive lights all show as amber, in the software it confirms all drives are operational and invites me to greate a volume and format which I obviously do not wish to do.

How do I go about rediscovering the RAID set?

Many thanks

Gary

*** Update ***
Having performed an extended SMART scan on the drives I can see that drive 1 of 4 is showing it has failed. However given this is a RAID-5 volume the NAS should still operate so I am unsure why it is not operatonal. Without the volume up I cannot replace the drive and rebuild the redundundancy.

Any assistance most welcome.

Gary
Title: Re: DNS340L appears to have forgotten raid-5 config
Post by: FurryNutz on December 14, 2017, 12:01:21 PM
Link>Welcome! (http://forums.dlink.com/index.php?topic=48135.0)


What Mfr and model is the main host router?

Please review this:
http://forums.dlink.com/index.php?topic=47326.0 (http://forums.dlink.com/index.php?topic=47326.0)
Title: Re: DNS340L appears to have forgotten raid-5 config
Post by: ivan on December 14, 2017, 01:42:55 PM
Hi Gary,

Your problem is one I have seen several times and the resolution is not easy.

You will have to forget most of what you know about RAID arrays on servers with dedicated raid hardware - nearly all small NAS boxes use a Software raid and as such can have serious problems if power is lost while the unit is running.

The fact that you have a faulty disk as well as a power failure has made recovery a lot harder.  The simple recovery method is to replace the faulty disk, reformat the array and restore from your backup. Then make sure the NAS is on a UPS.

The fact you are asking here indicates, I may be wrong and if I am I apologise, that you don't have a backup.  In that case you will need some recovery software, a lot of disk space to allow making a virtual raid array and have room for the data backup.  You will also need some method of connecting the disks to the computer you are using in the recovery operation.   

There is free raid recovery software available but I have never used it because it requires windows.  I have used the commercial R-Studio Raid recovery software because it has a Linux version and we needed to do a recovery of a problem similar to yours (without the damaged disk) but that was quite some time ago and I don't have the software - my old company does.  I will say that R-Tools Technology Inc do produce a quite detailed manual, presentations and online help to assist with raid array recovery.

Title: Re: DNS340L appears to have forgotten raid-5 config
Post by: niconux59 on February 07, 2018, 01:36:14 PM
Hi,

I'm having exactly the same issue but as far as I can see my RAID array (RAID 5 over 3 disks) is OK. As I still can connect on the box in SSH, I have been able to scan the disks :
Code: [Select]
/ # mdadm --examine --scan
ARRAY /dev/md0 level=raid1 num-devices=3 UUID=ebdd7a6b:9e1cbf5c:79f0c3a3:96a18951
ARRAY /dev/md/1 level=raid5 metadata=1 num-devices=3 UUID=603e7452:dd806ac8:1c3daac7:9671e5ca name=1

but the system don't see my data array :
Code: [Select]
/ # cat /proc/mdstat
Personalities : [linear] [raid0] [raid1] [raid10] [raid6] [raid5] [raid4]
md0 : active raid1 sdc1[2] sdb1[1] sda1[0]
      524224 blocks [3/3] [UUU]
     
unused devices: <none>

I have been able to assemble the array by recreating a /dev/md1 node (that is not created anymore at boot whereas /dev/md0 is) :
Code: [Select]
/ # mknod /dev/md1 b 9 1
/ # mdadm --assemble --run --force --update=resync /dev/md1 /dev/sda2 /dev/sdb2 /dev/sdc2
mdadm: /dev/md1 has been started with 3 drives.
/ # cat /proc/mdstat
Personalities : [linear] [raid0] [raid1] [raid10] [raid6] [raid5] [raid4]
md1 : active raid5 sdb2[0] sda2[2] sdc2[1]
      5855285760 blocks super 1.0 level 5, 64k chunk, algorithm 2 [3/3] [UUU]
     
md0 : active raid1 sdc1[2] sdb1[1] sda1[0]
      524224 blocks [3/3] [UUU]
     
unused devices: <none>

So I can mount my array, say on /mnt/test and access all my datas :
Code: [Select]
/ # mkdir /mnt/test
/ # mount /dev/md1 /mnt/test
/ # whatever_I_want on /mnt/test

But the box web interface is still saying "No Volume Found" ...

Where is it stored in the config that the array is mount at boot ?

Thanks in advance
Title: Re: DNS340L appears to have forgotten raid-5 config
Post by: niconux59 on February 07, 2018, 01:51:21 PM
I forgot to give some details :

If those informations can help in a diagnostic ...

Thanks again :-)
Title: Re: DNS340L appears to have forgotten raid-5 config
Post by: niconux59 on February 08, 2018, 09:18:19 AM
I think I'd better had opened a new thread ... sorry.

This is done : http://forums.dlink.com/index.php?topic=73088.0
Title: Re: DNS340L appears to have forgotten raid-5 config
Post by: FurryNutz on February 08, 2018, 09:26:38 AM
I recommend that you phone contact your regional D-Link support office and ask for help and information regarding this. We find that phone contact has better immediate results over using email. If in the USA, there is 24/7 online chat support.
Let us know how it goes please.