Parity Drive Recovery, I messed up

[mman360]

So I messed up and didn't read. 

 

I had to replace my USB drive so I had to rebuild my array. Not paying attention or reading I didn't think it would be an issue which drive I selected as my parity drive and mixed up 2 drive. (2 3TB data drive 1 3TB parity). 

 

Is there a way to recover the data using the old parity drive? It is currently not mounted since there's no file system. 

[trurl]

Not entirely clear but it doesn't sound good.

 

Go to Tools - Diagnostics and attach the complete Diagnostics ZIP file to your NEXT post in this thread.

[mman360]

mediaserver-diagnostics-20210831-1529.zip

[sheldz8]

When I first used unraid I accidentally chose the wrong disk for parity and I was unable to recover the 6tb data

Sent from my SM-A305F using Tapatalk

[trurl]

Disk1 is unmountable. Presumably this was the "old parity drive"? And I assume you built new parity on the "old disk1". Is that correct?

 

 

[mman360]

7 minutes ago, trurl said:

Disk1 is unmountable. Presumably this was the "old parity drive"? And I assume you built new parity on the "old disk1". Is that correct?

 

 

That is correct 

[trurl]

Have you allowed anything to be written to your server since then?

[mman360]

19 minutes ago, trurl said:

Have you allowed anything to be written to your server since then?

 

No I ended up pausing the rebuild and never wrote anything new.

[trurl]

But you have docker enabled, and appdata and system shares have some files on disk2, so maybe something got written to disk2 even if you didn't write anything yourself.

 

Which dockers do you have running?

 

[trurl]

7 minutes ago, mman360 said:

ended up pausing the rebuild

You let parity rebuild run for 50 minutes before that.

 

There is really only one thing to try and won't know how well it works until trying it. Follow these exactly and ask if you have questions.

1. Tools - New Config
2. Assign disks as they should have been
3. Check the box saying parity is valid
4. Check the box for Maintenance Mode
5. Start the array
6. Stop the array
7. Unassign disk1 (no device)
8. Start the array with Maintenance Mode box UNCHECKED and disk1 unassigned

After all that, disk1 will be disabled and emulated by the old parity and disk2, and we can see if it is mountable or can be repaired.

 

 

Post new diagnostics when done with all that and we will see what we have.

 

 

[trurl]

@mman360

 

Before doing any of that see my next post.

[trurl]

Are you absolutely sure you made the mistake you think? Or did you just assume you had made that mistake because disk1 was unmountable?

[mman360]

6 hours ago, trurl said:

Are you absolutely sure you made the mistake you think? Or did you just assume you had made that mistake because disk1 was unmountable?

 

Thanks for your help with this. I haven't moved forward yet. I assumed I made this mistake because it was showing unmountable due to no file system. 

[trurl]

3 minutes ago, mman360 said:

I assumed I made this mistake because it was showing unmountable due to no file system. 

OK

 

Lets see if filesystem check can find anything.

 

 

I assume the filesystem should be XFS, but diagnostics doesn't know what it was so it just says auto. You will have to set it to XFS to run the check.

 

Here is the wiki about filesystem check:

 

https://wiki.unraid.net/Manual/Storage_Management#Running_the_Test_using_the_webGui

 

 

and another post where somebody else was trying to check a filesystem that said auto:

 

https://forums.unraid.net/topic/105215-solved-unmountable-no-file-system-after-unclean-shutdown/

 

Study those.

 

Getting late so I may have to pick this up tomorrow or maybe someone else will.

 

 

 

[trurl]

@JorgeB @itimpi @JonathanM

 

I may not get back to this thread until after some sleep and other things so thought I would summarize in case anybody else wants to take it up.

 

The user may have mixed up parity and disk1 when reassigning disks. My plan was to try to get those disks reassigned correctly, then get disk1 disabled and try to rebuild it from parity.

 

But it may be that the disks were assigned correctly, and the real problem is just unmountable disk1, so checking the filesystem might work instead.

 

 

[sheldz8]

Can't this be fixed by removing the array settings?

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[JorgeB]

Click on disk1, set filesystem to xfs, then start array and post new diags.

[trurl]

5 hours ago, sheldz8 said:

Can't this be fixed by removing the array settings?

Depends on what you mean by "fixed". Do you not care about the data?

[sheldz8]

11 hours ago, trurl said:

Depends on what you mean by "fixed". Do you not care about the data?

Doesn't it just remove the array config instead of formatting? Everytime I reset my array config my data stays intact in the Cache and Array (I don't have parity drives)

[trurl]

1 hour ago, sheldz8 said:

Doesn't it just remove the array config instead of formatting? Everytime I reset my array config my data stays intact in the Cache and Array (I don't have parity drives)

Sorry, I didn't even notice that you weren't the OP when I replied before.

 

The OP does have parity and may have accidentally put a data disk in the parity slot and overwrote his data with parity for 50 minutes before noticing. How is resetting the array config going to fix that?

 

I guess I left that detail out of my summary.

 

[sheldz8]

6 hours ago, trurl said:

Sorry, I didn't even notice that you weren't the OP when I replied before.

 

The OP does have parity and may have accidentally put a data disk in the parity slot and overwrote his data with parity for 50 minutes before noticing. How is resetting the array config going to fix that?

 

I guess I left that detail out of my summary.

 

Yes, from your summary i read that it was unmountable and you wanted to get it reassigned correctly so when the array can't find the disk and a file system was assigned I usually just reset the array and reassign the disks correctly.