Started Data-Rebuild with Bad Parity? Help!!


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Hi,

I've created a compounded problem here and could use some assistance..
These things happened while adding some new drives to the server:
 

1. I accidentally pulled a mounted drive while the array was running (thinking it was an empty tray) and quickly popped it back in.
2. I installed 2 drives to the bay, a new unformatted drive and an old drive which i planned on wiping.
3. back in the WebGui I see the drive I accidentally unplugged has a red X "Device is disabled, contents emulated" (The new drives I added are in the unassigned devices section)
 

After reading through the forum - and this post:
https://forums.unraid.net/topic/51469-can-i-add-a-quotdevice-is-disabled-contents-emulatedquot-disk-back-in-to-the-array/
it sounded like this was typical for a drive connection issue, and at this point I'd need to either rebuild parity or the Data disk.
Since I don't have another drive that large (14tb) on hand and was pretty sure the drive was fine, I decided to follow the procedure to unassign, start array, stop array, re-assign, and rebuild data from parity.
 

Upon starting the rebuild, I noticed that none of shares from that disk were visible.. in the GUI nor on the network.
My recollection of prior migrations was that the emulated contents would be preserved in parity and at least readable while the rebuild is in progress?
 

Then I realized, the old drive I'd added (which still had data on it) had MOUNT info 
and in fact, this was the old drive(2TB) that I migrated FROM, long ago...  TO the current disk in question (14TB).  (they both occupied same slot #8)
Is it possible that parity got confused during the removal/install of drives and caused it to be overwritten?  


After about 2% into the rebuild process I decided to pause and eventually cancel and take the array offline until I figured things out.


So.. in a bit of a panic here,  I can't afford to lose this data.
Can someone verify that i SHOULD be seeing the shares during the rebuild/emulation?
 

If that is true, then I'm assuming I have screwed up parity...?

and having started a data rebuild on top of that,  how much damage has been done? I'm assuming not as bad as a reformat,
but that I'd need to use something like UFS Explorer to retrieve the data and copy onto a new disk?


Any advice on how to safely proceed, much appreciated.

- thx

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There was some confusion because of the duplicate filesystem on the unassigned disk, if you leave the disk to rebuild assigned and reboot it should mount correctly when it starts a new rebuild, if it doesn't post new diags.

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After powering down last night, I pulled the drive in question to try scanning with UFS explorer.  It's about halfway through the scan.
I have another large drive on the way - would prefer to rebuild on that one.

In the meantime, would it be safe to boot with no drive in slot #8 ? (and without the unassigned drives)
in order to just see if parity shows the missing disk8 data correctly?

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So,  rebooted without disk and {relief}  ..parity is intact. Can see all shares and data.
I think from here should be okay.. just need to do the rebuild.
Thanks much for your helpful insight.

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