Force Read Only Array Mount with Old Parity Drive

[Kevin T]

1 minute ago, Kilrah said:

Do a New Config again so it forgets any previously assigned disks

 

I've tried that 3 times but it didn't change anything.  I was originally advised to Retain All current configuration so that is what I'm doing.

[JorgeB]

Make sure you are clicking "apply"

[Kevin T]

No wonder, I was hitting Done instead of Apply, now I can configure.  I must have been overly anxious.

 

But I tried starting the array with the old Parity disk, removing the substituted Disk 1 and it won't mount (says Unmountable: Wrong or no file system), so I stopped the array and started in Maintenance mode and this is all I am getting:

 

root@unRAID:~# xfs_repair -v /dev/md1
Phase 1 - find and verify superblock...
xfs_repair: error - read only 0 of 512 bytes
xfs_repair: data size check failed
xfs_repair: cannot repair this filesystem.  Sorry.

 

[JorgeB]

Post new diags.

[Kevin T]

Here's the diagnostics.

unraid-diagnostics-20221016-0335.zip

[JorgeB]

After array start, in normal mode.

[Kevin T]

I did originally try in normal mode and it said Unmountable: Wrong or no file system so then I stopped the array and started it again in Maintenance mode and this was all I got:

 

root@unRAID:~# xfs_repair -v /dev/md1
Phase 1 - find and verify superblock...
xfs_repair: error - read only 0 of 512 bytes
xfs_repair: data size check failed
xfs_repair: cannot repair this filesystem.  Sorry.

 

The xfs_repair barely did anything, it ran for only about a second or so.

 

I find it weird it's not doing anything because this is the Parity drive I did a size upgrade on before anything started going wrong.  The only thing I've done on the other 3 data drives is run xfs_repair checks on them but I haven't written any data to those drives.

[JorgeB]

12 hours ago, Kevin T said:

I did originally try in normal mode and it said Unmountable: Wrong or no file system

Yes, but I would still like to see the error, though probably not much that can be done.

[Kevin T]

Here's the screenshot, I also ran fdisk if that helps at all.

 

root@unRAID:~# fdisk -l /dev/md1
Disk /dev/md1: 4.55 TiB, 5000947249152 bytes, 9767475096 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes

[Kevin T]

Just following up on my previous message, thanks.

[JorgeB]

You still haven't' posted the diags after array start.

[Kevin T]

Oh I didn't realize there were different stages of diagnostics as I posted one on Sunday.  Here is a current one while the array is running.

unraid-diagnostics-20221019-0320.zip

[JorgeB]

This is why it's not working:

Oct 19 03:19:34 unRAID kernel: mount: attempt to access beyond end of device

It might work with a larger replacement device, of course it would require parity be upgraded first.

[Kevin T]

Why would it be asking for a larger drive when the original Disk 1 was 5TB?  Does it have something to do that my temporary substitution 5TB for Disk 1 to restart the array is showing larger than my other 5TBs for Disks 2/3 (see images on page 2, 2nd to last post).

 

I have a larger drive available, how can I upgrade the parity with a failed drive?

 

 

Edited October 19, 2022 by Kevin T

[itimpi]

2 minutes ago, Kevin T said:

I have a larger drive available, how can I upgrade the parity with a failed drive?

You could use the Parity Swap procedure.

[Kevin T]

I'm doing a Parity Swap right now and it's copying the parity to the new drive, so after it's done, what is the best next step?  Not sure if I just try again and do the drive substitute on Disk 1 then remove to see if it will mount / emulate or do I just assign the original parity to Disk 1 (which is the exact model/size as my original Disk 1 that failed) and go from there. 

[JorgeB]

Parity swap will use the old parity for the disabled disk, but that won't work in this case since it will be the same size as the previous one, you'd need to then rebuild again to a new larger disk.

[Kevin T]

So how do you upgrade the parity?  itimpi said to use Parity Swap so that's what I did.

 

My original Disk 1 is not recognized by BIOS, so how can I rebuild?

 

My new disk for the parity swap is 6TB and the original was 5TB.  The only 5TB drive I was able to get ahold of for the temporary Disk 1 to use to disable is slightly larger than my other 5TB drives even though it is 5TB as well so I figured that is what is throwing the error.  After the parity swap is complete I'm hoping to be able to use that 5TB instead for the temporary drive since it is the same make/model/size as my other 5TB drives and the one that failed.

I'm still trying to emulate DIsk 1.

[JorgeB]

8 hours ago, Kevin T said:

So how do you upgrade the parity?  itimpi said to use Parity Swap so that's what I did.

And that is correct and the first step, then you'd need to upgrade disk1 to a larger one.

[Kevin T]

So the 5TB drive that was the parity drive won't work as a replacement?  Can I emulate it initially?  How can I upgrade it if it's not finding a filesystem and wouldn't mount?

[JorgeB]

59 minutes ago, Kevin T said:

So the 5TB drive that was the parity drive won't work as a replacement?

It works but it will have the same issue as the current disk, since it's the same size.

 

 

[Kevin T]

I'm not understanding if the Disk 1 that failed was originally 5TB why do I have to replace it with a larger drive?  And is that just for it to be (hopefully) mounted and emulated using the New Config process?

 

 

Edited October 21, 2022 by Kevin T

[itimpi]

Just now, Kevin T said:

I'm not understanding if the Disk 1 that failed was originally 5TB why do I have to replace it with a larger drive?  And is that just for it to be (hopefully) mounted and emulated?

When checking disk sizes Unraid works on the EXACT size, not the rounded off one.   even 1 byte difference in reported size is significant.

[Kevin T]

9 minutes ago, itimpi said:

When checking disk sizes Unraid works on the EXACT size, not the rounded off one.   even 1 byte difference in reported size is significant.

 

So did the 5TB external temporary replacement drive showing larger in bytes compared to all my other 5TB ones essentially cause this?

 

The 5TB Seagates originally installed are 4,883,770,532 KB (XFS)

The 5TB WD external is 5,860,522,532 KB (partition unknown but NTFS)

 

I don't understand the large discrepancy if they are both 5TB

 

Edited October 21, 2022 by Kevin T

[JorgeB]

30 minutes ago, Kevin T said:

I'm not understanding if the Disk 1 that failed was originally 5TB why do I have to replace it with a larger drive?

Because of this:

 

On 10/19/2022 at 11:25 AM, JorgeB said:

This is why it's not working:

Oct 19 03:19:34 unRAID kernel: mount: attempt to access beyond end of device

It might work with a larger replacement device, of course it would require parity be upgraded first.

 

XFS thinks the partition is larger and that's why xfs_repair doesn't work, but like mentioned it *might* work with a larger disk, it's not something I can test.