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Possible two drive failure with one parity drive. "Unmountable: wrong or no file system". Need help.

Featured Replies

Hello everyone. 

 

A couple of weeks ago one of my four array drives died and I've been emulating that drive with parity drive for the time being before I god the replacement drive. 

I just right now received the new drive, but just before I was going to get it, yesterday another one of my drives suddenly stopped working. 

In the array it shows up as "Unmountable: wrong or no file system". When the previous drive died it didn't show up like that, it just gave me I/O errors and gave me warnings, etc. This one just showed up like that out of the blue. 

 

So right now I have Disk1 and Disk2 working properly. Then the Disk3 is "Unmountable: wrong or no file system". And then Disk4 is unassigned and emulated with parity drive. 

 

I actually had way more data on Disk3 than the Disk4 (Disk4 was a recent purchase, like a month or two ago, about 2-ish TB used from 12 total, while 12TB Disk3 was almost all the way full) 

 

What do I need to do to fix the situation? 

I don't even know what kind of logs to post here for anyone to help me out, but i really need help though. 

  • Author
On 3/2/2025 at 2:55 PM, JorgeB said:

Please post the diagnostics.
 

Sorry for a late reply. Here is the diagnostics attached. 

I am in the same situation still. Haven't touched the array. 

Disk 3 is still "Unmountable: wrong or no file system" and Disk 4 is still unassigned but accessible (via parity) 

 

I also have currently a new disk that i haven't plugged in to the system yet. 

 

 

Edited by THEVAN3D

  • Community Expert

See if disk3 imports read only, post the output from:

zpool import -o readonly=on disk3

 

 

  • Author

this is the output i got from that 

image.png

  • Community Expert

I'm afraid the pool is gone, you'll need to restore from a backup, if there's no backup, you can try a file recovery app, like UFS explorer.

  • Author

do you mean array by chance? because there is no problem with my cache pool. 

 

still have couple of questions though. 

 

like how could this have happened in the first place? i mean disk4 was maybe faulty, it gave me bunch of errors couple of weeks ago, ok, but disk 3 worked fine, didnt have any errors. it just unassigned itself one day and that's it. no prior warning. 

 

so what do i do now? do i just toss them both out? or how do i check if the disk3 is still healthy or not? 

 

and finally for the future, how do i monitor my drives properly so i have time to prepare for their death and buy a replacement one? 

  • Community Expert
11 minutes ago, THEVAN3D said:

do you mean array by chance?

I mean that zfs pool, disk3.

 

11 minutes ago, THEVAN3D said:

like how could this have happened in the first place?

Difficult to say for sure, but zfs getting corrupt without an apparent issue, is in my experience, it's most often caused by a hardware issue, like bad RAM, or a device firmware problem for example.

 

Dis4 is just disabled, you just need to rebuild, SMART looks fine, recommend replacing cables first, to rule that out.

 

 

 

 

  • Author
20 minutes ago, JorgeB said:

I mean that zfs pool, disk3.

 

Difficult to say for sure, but zfs getting corrupt without an apparent issue, is in my experience, it's most often caused by a hardware issue, like bad RAM, or a device firmware problem for example.

 

Dis4 is just disabled, you just need to rebuild, SMART looks fine, recommend replacing cables first, to rule that out.

RAM is fine. Did a full successful memtest scan for about 7-8 hours about a month ago when disk4 first started giving me the errors. 

 

All the sata data cables are also brand new ones that came with motherboards and the power cables are from the psu directly, high quality. 

But I was using some cheap-ass 90 degree adapters though, maybe they caused the problem(?) but i threw them away now. everything is direct connection. 

 

 

 

 

So what is my next move now? How can disk4 be rebuilt if disk3 is missing? isnt that needed for parity to rebuild the disk4? 

And if i put the new disk in place of disk4 and i rebuild it, then what do i do with the disk3? is it all lost? 

  • Community Expert
5 minutes ago, THEVAN3D said:

RAM is fine. Did a full successful memtest scan

Keep in mind that memtest is only definitive if it finds errros.

 

Disk3 is not missing, just unmountable, you can still rebuild disk4.

 

You can also attempt to re-format disk3, but any data there will be lost.

  • Author
26 minutes ago, JorgeB said:

You can also attempt to re-format disk3, but any data there will be lost.

Alright, so i can now rebuild the disk4 on the new drive and then reformat disk3 and see if it works. Thanks. 

 

and how do i monitor the drives in the future? any plugins i should have installed to frequently monitor health automatically? 

or how to properly check the disk3 afterwards? i really want to make sure all my drives are fully healthy. 

  • Community Expert

Both cases don't look a drive problem, but if you enable system notifications you'll get notified of any read/write errors, as well as any changes for the monitored SMART attributes, for filesystem issues there are no notifications, but the issue should be clearly visible when looking at the GUI, or trying to access that data.

  • Author
4 minutes ago, JorgeB said:

Both cases don't look a drive problem.

Wait a minute. You think both of my drives can be healthy? and it was due to bad cable/adapter or ram or something else? 

  • Community Expert

Disk4 appears to have been disabled due to a power/connection problem, issues with disk3 are filesystem problem, not a device problem.

  • Author
12 hours ago, JorgeB said:

Disk4 appears to have been disabled due to a power/connection problem, issues with disk3 are filesystem problem, not a device problem.

i removed disk4. installed new disk in its place and started rebuild process. hope it goes well fully. 

and after that, is there anything i can do to fix the filesystem on disk3? or is formatting the only way? 

  • Community Expert

There is no fsck for zfs, it would need to be reformatted.

 

 

  • Author

Finished rebuilding disk4 onto the new drive that i had successfully. 

Then I stopped the array, removed disk3 and started array like that. 

Then I stopped it again and re-added disk3 again and now it started rebuilding disk3 too, but it is still showing up as "Unmountable: wrong or no file system"

image.thumb.png.a93f4f31cd6c6ff27f13fcf6488579f4.png

 

Does this make sense? Is there even a chance for this to actually complete? 

  • Community Expert

You didn't need to rebuild, just format, format button is next to array stop button.

  • Author
34 minutes ago, JorgeB said:

You didn't need to rebuild, just format, format button is next to array stop button.

i thought there was a chance for it to recover data :(

  • Community Expert
On 3/5/2025 at 12:54 PM, JorgeB said:

You can also attempt to re-format disk3, but any data there will be lost.

 

  • Author
1 minute ago, JorgeB said:

You can also attempt to re-format disk3, but any data there will be lost.

yes, i know you told me that, i just thought you meant the data can not be rebuilt so i had to format it because of that... but it is rebuilding now. 

or at least i think it is.. is it not? i mean its doing something. all the disks are active at about 250MB/s doing something. 

should i just give up and cancel this? 

  • Community Expert

It's rebuilding, but it's rebuilding the same corrupt filesystem, if there's data there that you want to try to recover 

On 3/5/2025 at 11:36 AM, JorgeB said:

you can try a file recovery app, like UFS explorer.

 

  • Author

ok. whatever. f* it. i formatted it. 

but now that drive is emulated too. 

how do i re-add it properly to the array? 

 

and also, do you think my old disk4 is worth keeping again? i'm so afraid it is actually dead or defective. it had one crc error too before btw. 

  • Community Expert

Since you've started a rebuild, you will need to let it finish.

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