Array issues - Failed disks

[wishie]

So, im in a bit of a tight spot.. 

 

I've got an array of 7 disks, but with one (disk 1) in a failed state, and another (disk 3) starting to show read errors.. Now, I want to replace the failed disk and rebuild parity, but the issue is, my new replacement disks are larger than my current parity disk.

 

I am at a loss of which order to attack things. My parity drive (and therefore also my largest data drive) is 2Tb. I do have a 'spare 2Tb' drive, with no data on it anymore, BUT, its part of the array (disk 7).

 

Is there a way to remove disk 7 from the array, and reassign it to slot 1, rebuild parity, then replace parity disk, then replace the disk with read errors (disk 3) ?

 

Or, what do you think my best course of action is in this situation?

[wishie]

Ok, I've found a tutorial on how to upgrade the parity, so I'm going to do that first.. then I will 'shrink' the array, by removing disk 7, and then put it in the slot of the failed drive, and rebuild it from parity. After that, I will install another new 3Tb drive to replace one of the oldest disks (yet still working perfectly, a 1Tb SAMSUNG drive).

 

It seems the read errors on disk 3 were to do with it being an older rieserfs formatted disk, and it being very full. Removing some data from it seems to have made the errors go away, and there are no SMART errors for that drive.

[itimpi]

You cannot simply upgrade the parity disk with a failed drive also present.    You also cannot remove a disk from the array without invalidating parity (and thus the ability to recover an already failed disk.

 

i think from your description that you will have to follow the ‘parity swap’ procedure that allows you to simultaneously upgrade parity and rebuild a failed drive.   However you should provide more information to be sure.    In particular you should provide the system diagnostics zip file (obtained via Tools->Diagnostics) which is always of help to those trying to diagnose your problem and the best way forward.

[wishie]

That's what I am doing.. the 'parity swap' to a larger drive, and obviously using the old parity drive to replace the failed one.

 

[wishie]

So, a bit of an update..

 

The 'parity swap' to the larger parity drive, and the subsequent  data drive rebuild worked perfectly. No errors at all, everything back working 100%.

 

To be honest, when I had a failed data drive, and no suitable replacement drives (all my replacements were larger) I assumed I was looking at data loss. This 'parity swap' feature (and unRAID in general) have saved my bacon.

 

Now, my next steps are going to be replacing all my reiserfs drives with XFS formatted ones.. there is a way to do this without parity rebuilds each time, right?

Edited November 14, 2017 by wishie