Failed Disk in ZFS Raid 10 array.

[akaVintz]

Hi everyone,

I had a failing disk in my Raid 10 initially I got an email saying "Device: /dev/ada2, unable to open device"

After a reboot of the NAS it came back but was making a aweful racket and reported as having unreadable sectors. I physically removed the disk and replaced it.

The webgui showed the disk id as being unavailable with the message "used to be", and the original disk id.

I chose to detach the removed disk from the array, probably the wrong thing to do as I now have a Raid10 array which is showing as healthy but I only have three disks in it, one mirror consisting of two disks and a stripe consisting of one disk.

I thought I would be able to online the new disk and attach it but I am getting an error using volume manager and extend which I think is suggesting I can only add a pair of disks to the array.

I also thought maybe about removing the disk I have left in the second mirror, effectively leaving just one mirror and then extending the array with the two unused disks. But offlining it gives an error "no valid replicas.

I really dont want to lose any data on the array.

Can anyone suggest a solution?

Thanks in advance for any help you can offer.

Freenas 8.3.1 Release p2

Vince

 

[SweetAndLow]

So you should have followed the step's outlined in the manual. At this point you need to backup your data and rebuild your pool. After you have striped the data with a single drive I don't think there is any going back.

 

[Ericloewe]

Actually, there's still hope. You can add mirrors to single disks. I didn't know the GUI even let you remove mirrors... You'll have to undo the damage from the CLI. Search for the instructions.

In any case always follow the manual's disk replacement instructions to the letter. There's a very good reason they're there. Don't start inventing "solutions".

 

[akaVintz]

I detached it from the cli!

The only command I can find is zpool attach <pool> <original disk> <new disk> but as I have removed the old disk i dont have the guid for the <original disk>

http://aarononeal.info/freenas-convert-an-encrypted-disk-to-mirror/

V

 

[Ericloewe]

The pool is encrypted? Destroy it and rebuild it.

And again, do not use the CLI unless specifically told to.

 

[akaVintz]

No its not encrypted but that was the closest I got by googling.

 

[Sir.Robin]

You haven't lost any data yet, so if you have no backup as of now... I would urge you to make one asap.

You ned to "replace" a disk before "detach".
Not having done so, i don't know if it can be fixed.

Backup and then destroy/rebuild your pool.


Sent from my mobile using Tapatalk

 

[akaVintz]

OK Thanks guys. Im backing up and ill destroy and rebuild the array.

 

[rs225]

Good to have a backup, but you don't have to destroy this pool. The attach command needs the guid for the remaining original disk, not the detached original disk.

 

[Sir.Robin]

Good to know! :)


Sent from my mobile using Tapatalk

 

[akaVintz]

Good to have a backup, but you don't have to destroy this pool. The attach command needs the guid for the remaining original disk, not the detached original disk.

RS225.

Can you elaborate? I just looked at the command and its
usage:
attach [-f] <pool> <device> <new-device>
Thanks
Vince

 

[akaVintz]

Thanks for all your advice guys, I ended up trashing it and moving over to RaidZ2.