Hi Folks,

Kinda find myself in a bind, and wondering if I'm already buried alive... :/

Have a 3-disk server, 2 data 1 parity.

One of the disks (Disk 1 old) showed as "unreadable" in the main view so I replaced it with a new drive (Disk 1 new) (still have the old one unadulterated)

Rebuilt (disk 1 new) as per normal process, which went fine and as expected, but (Disk 1 new) also ended up showing as "unreadable" and in a bad move, I formatted it, likely with the array still live.

No surprise, now data that was on "Disk 1" is gone.

Do I have any recourse here? Having (Disk 1 old) which must have had some bad sectors someplace, but with all the data, (Disk 1 New) which rebuilt, but ended up with the same "unreadable" as (Disk 1 old), but which I then formatted. The parity disk (which must have noticed the formatting) and the unadulterated "Disk 2".

Is there a way to attempt to recover parity or some other operation which could salvage much of the info from Disk 1 old, get it back into parity, and then insert a fresh drive for the rebuild process?

I'm tech savvy, but not unraid savvy, and after messing this up, I'm very gun-shy about what to try next.

Any learned advice would be greatly appreciated!

If you have enough ports, plug original disk1 in but leave unassigned.

Start the array, then

Attach Diagnostics ZIP to your NEXT post in this thread.

OK, just so I'm clear...

Remove (new disk 1)

Insert (old disk 1)

(Perhaps enable array)

Download "Diagnostics".

I'm curious, since I formatted a "disk 1" would the parity try to "rebuild" this disk when I insert it?

Would it be safer to remove the parity disk to reduce risk of overwriting the old disk 1?

Can the "diagnostics" be read with the array disabled?

Apologies for the additional questions... just trying to be quite careful since much of this is opaque to me! :)

Gratefully,

ken

You should not need to remove the new disk1 What you are trying to do here is see if the old disk1 can be mounted by the unassigned devices plugin.

In your earlier posts you mentioned a drive showing as 'unreadable? This is not a standard Unraid status so did you mean 'Unmountable'? Checking so we can be sure when trying to give advice.

5 minutes ago, MrKenSan3 said:

since I formatted a "disk 1" would the parity try to "rebuild" this disk when I insert it?

Unraid treats a 'format' like any other write operation and updates parity to reflect that the format has happened.

Yes, Unmountable is probably what I saw...

I've included a diagnostics dump with only the original two disks installed and no parity.

I am too paranoid about the original disk being messed up (further?) to risk it! Please let me know if this is enough info to shed insight.

Gratefully,

ken

rock-diagnostics-20250820-1332.zip

1 hour ago, itimpi said:

Unraid treats a 'format' like any other write operation and updates parity to reflect that the format has happened.

So, based on this, the Parity is basically cooked now?

ie. it no longer has value in terms of recovery of the data, correct?

My only chance seems to be the (old Disk 1), correct?

9 hours ago, MrKenSan3 said:

My only chance seems to be the (old Disk 1), correct?

You might find that a file recovery program like UFS Explorer on Windows can still recover data from the newly formatted/rebuilt drive. It is not free for actually recover data but does have a free option for checking the drive to show what it thinks is recoverable.

I would think trying your get the data of the old drive via Unassigned Devices is your best bet (and the least effort to try).

Thanks, only I don't know what that means exactly.

My suspicion is that indeed, the original Drive 1 is more likely to yield fruit than the new one... unformatting is a messy and inexact process.

So, from the sounds of it, consensus is more or less work on the original drive, give up on parity or any "unraid" style strategies?

Appreciate your thoughts!

Have you tried the suggested option of trying to mount the original drive with Unassigned Devices? If so what was the result?

Hi Itimpi,

I'll try your suggestion, I just don't understand exactly what you are suggesting. ie. terminology.

I don't know what you mean by "mount the original drive with Unassigned Devices". Conceptually I do, but operationally don't know what the means in terms of Unraid.

Is there a page within the UI which has such an option, or are you suggesting just opening a shell and using the mount command?

Thanks for the clarification! And your continued assistance and suggestions!

Gratefully,

ken

22 hours ago, MrKenSan3 said:

I've included a diagnostics dump with only the original two disks installed and no parity.

So do you mean that the old disk1 is installed (and assigned as disk1?), and the new disk that you intended to replace it with is not installed?

Almost.

The diagnostics are collected with "Old Drive 1" in the chassis, and Drive 2. Parity is removed.

The array, of course, does not start in this configuration. (As I mentioned, I am paranoid now about losing what might be recoverable on Old Drive 1)

"New Disk 1" (which was formatted with the array active Doh!) is NOT installed.

I'm just looping around to spending time on this again, as I've had to also pay attention to the "day job" ;)

Much thanks for your insights.

ken

Hi Guys,

OK... Here's the story, now that I've been able to dig in a bit...

1. I just went into the shell and mounted (Old Disk1) and the OS seemed to do this without complaint, and the filesystem seems in-tact (at least a quick couple directories check) Good News! :)

2. I've ordered a "spare HDD" which I'll use to just back up Disk1 and Disk2 data onto... before trying to restart the array. (I have backups, just not capturing a flurry of recent work, so doing so now before messing around seems like a good idea)

3. I'll also check the filesystems on Old Disk1 and Disk2 after the copy/backup, and before trying any unraid operations.

So next questions...

a. What does the error "Unmountable" mean, exactly? I clearly (and naively) misinterpreted this as a "problem with the disk", however perhaps this means something else? (disclaimer, been under the gun on work stuff, so was trying to be proactive in terms of replacing the disk and moving on).

b. When "New Disk 1" was rebuilt from parity (before I formatted it), it had the same "Unmountable" moniker. Makes sense since the rebuild was a sector-by-sector reconstruction of the disk from parity and Disk2!

c. After I have backed up the data off of the drives, and I'm ready to get the array going again, what would be the best procedure for assuring that the two data drives are mounted without adulteration, and that it's the PARITY drive which is rebuilt?

An aside (which led me to assuming it was a disk problem) is that in the former logs (which seem gone now), there were some kind of "checkum error" in the logs, which I interpreted as being caused by disk failure of some sort... I am now more unsure than ever about what those errors really mean. Sadly, it seems former log files are cleaned/purged upon power cycle, so dunno how to reproduce those.

My concern is that these errors had occurred quite a while in the past (months!), and so my assumption was that the array was running on only the Disk2 and Parity. The UI (as I interpreted it) seemed to indicate it was ignoring Disk1, or had kicked Disk1 out of the array.

This said, I have looked at dates on the directories on Disk1, and dates seem to have been updated all the way to about the time I ordered the new drive (and shut the array down to prevent damage). So, this means that Disk1 was still participating and being updated the whole time, despite the errors being reported in the UI.

The thing that led me to look in the first place was that some docker plug-ins stopped working... this led me to look at the system and discover the problems... so kind of a "rabbit hole".

While it seems no (or at worst little) data lost, I would deeply appreciate you guys helping me interpret/understand the messages and behavior so I can better address this in the future. Also, please note, I've been using Unraid for decades (since it was Lime), and this is the first time I've experienced this kind of confusion/problem. I did have a failing disk once, but simply replaced it, and as expected, all was rebuilt and life moved on.

Once again, Grateful for your help in understanding things.

ken

11 hours ago, MrKenSan3 said:

What does the error "Unmountable" mean, exactly?

Typically means there's a filesystem issue, that can most often be resolved with check filesystem.