Two data HDDs of the Array (out of 3) suddenly unmountable (1 parity disk) - how to recover data ?

[ullibelgie]

As a new user of Unraid, I was busy to build my server with all the data... finally it is finished for a couple of days and I am now about to make my first backup:

- 1 parity disk (1Tb)

- 3 Array HDDs (1Tb each)

about 55% of space used by data

 

No Cache drives or any pools

Apps : Paperless ng, Calibri

 

But now I have a fundamental problem:

2 of the data disks are suddenly unmountable

only one disk remaining plus the parity disk

 

So most of the data not accessible....

I have found some information in the Unraid Docs  https://wiki.unraid.net/Manual/Troubleshooting#Unmountable_Disk.28s.29

However what to do, if not only one, but two disks become unmountable (2/3 of all data )

 

Any advice, what to do to recover the data ?  Thank you

 

Diagnostic file attached...

 

 

tower-diagnostics-20210807-1443.zip

[itimpi]

That link is for handling an unmountable disk, and you can do a disk check/repair on each drive individually 

 

[ullibelgie]

As I have 2 (out of 3) array disks failing, the array configuration is signed invalid and I cannot restart it in maintenance mode.

According to the 'lost array configuration' advice in the Unraid wiki https://wiki.unraid.net/Manual/Troubleshooting#Lost_Array_Configuration

the data should not be lost.

I also have a flash drive back-up from some hours ago, with no re-assignment of disks

Also I still have a parity disk, which is not disappeared...

 

So because I still have the parity disk and the recent flash back-up, is there are more easy, but still save way for recover the both disks and rebuild the array configuration, so I can start it up (in maintenance mode to check file systems of the two disks)

 

Screenshots of the array from UD main page attached.

 

Thanks for help

 

 

 

 

[ullibelgie]

I rebooted the Unraid server - the failed disks do not even appear in Unassigned disks any more:

 

 

However I can see them as missing in the array:

 

 

Is there a realistic chance to recover the data on disk2 and disk 3 ?

They could not be mounted earlier and now disappeared.

 

What should be the next step ?

Some sort of checkdisk outside of Unraid ?!

 

 

[itimpi]

There will be no chance of recovering 2 drives that have really failed with only a single parity drive.  Have you tried power cycling the server to see if they can be seen then?    If not there will not be much chance of recovering the contents on any system if the drive cannot even be seen.

[trurl]

Go into the BIOS and see if you can set that controller to ahci mode

Aug  6 09:25:58 Tower kernel: scsi host1: ata_piix
Aug  6 09:25:58 Tower kernel: scsi host2: ata_piix
Aug  6 09:25:58 Tower kernel: ata1: PATA max UDMA/100 cmd 0x1f0 ctl 0x3f6 bmdma 0x1880 irq 14
Aug  6 09:25:58 Tower kernel: ata2: PATA max UDMA/100 cmd 0x170 ctl 0x376 bmdma 0x1888 irq 15
Aug  6 09:25:58 Tower kernel: ata2: port disabled--ignoring
Aug  6 09:25:58 Tower kernel: ata_piix 0000:00:1f.2: MAP [ P0 P2 P1 P3 ]
Aug  6 09:25:58 Tower kernel: scsi host3: ata_piix
Aug  6 09:25:58 Tower kernel: scsi host4: ata_piix
Aug  6 09:25:58 Tower kernel: ata3: SATA max UDMA/133 cmd 0x18b0 ctl 0x18a4 bmdma 0x1890 irq 19
Aug  6 09:25:58 Tower kernel: ata4: SATA max UDMA/133 cmd 0x18a8 ctl 0x18a0 bmdma 0x1898 irq 19

 

[ullibelgie]

Thanks for replies !

Indeed I do not think, that there is any fault of the HDD's itself, but the Sata-controller (on motherboard)

Because by using different sata ports on the Supermicro X7DVL-E board for the 4 HDDs, I could manage to see 3 disks in the array - so only one missing.

However the fourth disk I cannot get visible. The check routine of Unraid to check the file system doesn't repond anything.... I guess, because of a hardware fault of the Sata controller itself - so there is no data connection at all to the missing 4th HDD.

I will tomorrow check, if I see anything strange in the BIOS - I thought I had enabled AHCI...

 

Will check it tomorrow, after a good sleep..... many thanks.

 

If I cannot find anything, I think I have a broken motherboard and I simply need to build new hardware. In that case, I will keep the HDDs to transfer everything on the new hardware, when it is ready.... however it will be hard to find budget immediately for a new server...but that is a different story.

[ullibelgie]

I found indeed for some reason the I/O settings in BIOS was set to AHCI disabled. I don't know, if this was set ealier to enabled or not, when installing Unraid.

Additionally I found (with AHCI disabled mode) that when I changed the cables to use different SATA ports on the X7DVL-e Motherboard different HDD got disabled. But as I managed to get 2 (out of 3) data disks enabled plus one parity drive, I was able to repair the XFS file system with the steps explained in the unraid wiki (look in the manual under trouble shooting)

After that I could also mount the remaining 3rd data disk

Then the rebuild process started...

It looks to me, that the rebuild process was successful (look at the screenshot below)

 

However there were 180 errors of a different data disk!

Are these new errors ? Or errors which occurred sometimes during the total life time of the HDD - even years ago, when I started to use it in my old windows machine.

Total lifetime is now almost 1600h

Better to exchange the disk 1 ?  As my parity disk is also only 1Tb... better to buy a bigger parity drive also for the future possible expansion...

 

Many thanks for the people who helped me with this problem.