[SOLVED] Parity drive toast

[Theldron]

Hi all,

 

Upgraded a 1tb drive in my array to 2tb and it started the rebuild, now I have around 400 errors on my parity drive.

 

I know I need to replace the drive asap, but would some data be corrupted?

 

I have attached my diagnostics.

 

Cheers

gamingnas-diagnostics-20200429-2103.zip

[Theldron]

Hi all,

 

How do I replace the parity drive? Do i need to do a parity check before replacing it?

 

 

Any help would be appreciated

[itimpi]

8 minutes ago, Theldron said:

Hi all,

 

How do I replace the parity drive? Do i need to do a parity check before replacing it?

 

 

Any help would be appreciated

Just stop the array, assign the new parity drive in place of the old one and restart the array to build parity onto the new drive.    No point in doing a parity check as you are about to discard the current contents.

 

[Theldron]

Sorry just to double check is the process the same as a data drive? With stopping the array unassigning the disk, power down, replace drive, start server, assign parity drive, start array?

 

Thanks mate.  Do you think there is a chance of data corruption?

[itimpi]

1 hour ago, Theldron said:

Sorry just to double check is the process the same as a data drive? With stopping the array unassigning the disk, power down, replace drive, start server, assign parity drive, start array?

 

Thanks mate.  Do you think there is a chance of data corruption?

Yes - that is the correct procedure.    The only difference is that in this case it will be building new parity based on the data drives rather than trying to rebuild the data on to an array data drive.    

 

There should be no corruption unless you already have corruption on the data drives.    Parity will be built to correspond to whatever is already on those drives.

[JorgeB]

3 hours ago, Theldron said:

Do you think there is a chance of data corruption?

Rebuilt disk will likely have some corrupt data, unless by chance the read errors on parity coincided with empty sectors on disk2, if you still have the old disk use it to re-sync with a new parity then upgrade again.

[itimpi]

49 minutes ago, johnnie.black said:

Rebuilt disk will likely have some corrupt data, unless by chance the read errors on parity coincided with empty sectors on disk2, if you still have the old disk use it to re-sync with a new parity then upgrade again.

I missed the fact the parity drive failed during rebuild .

 

if the original 1TB drive is still intact then it might be best to assume the rebuilt drive2 has nothing useful on it?   You can check if the 1TB drive mounts under Unassigned devices and appears to contain the expected data..    In which case the thing to do will be to get the array back into a useable state with valid parity and then reformat disk2 to set it back to empty and copy the data from the 1TB drive.

[Theldron]

 

1 hour ago, johnnie.black said:

Rebuilt disk will likely have some corrupt data, unless by chance the read errors on parity coincided with empty sectors on disk2, if you still have the old disk use it to re-sync with a new parity then upgrade again.

Hi both, thanks for that.  I still have the 1TB drive, in a USB docking station ready to clear - glad I held off.  How would I go about doing a re-sync?

 

31 minutes ago, itimpi said:

I missed the fact the parity drive failed during rebuild .

 

if the original 1TB drive is still intact then it might be best to assume the rebuilt drive2 has nothing useful on it?   You can check if the 1TB drive mounts under Unassigned devices and appears to contain the expected data..    In which case the thing to do will be to get the array back into a useable state with valid parity and then reformat disk2 to set it back to empty and copy the data from the 1TB drive.

From what I remember the 2nd drive was barely used in the array. I still have the 1TB drive - phew!!!  So could I copy the data straight from the 1TB to the 2nd 2TB drive in the array once it is all back up and running, from the docking station as I am using all my sata ports on the motherboard?

 

I have just ordered a new 2TB drive to replace the parity.

 

[Theldron]

3 hours ago, itimpi said:

Yes - that is the correct procedure.    The only difference is that in this case it will be building new parity based on the data drives rather than trying to rebuild the data on to an array data drive.    

 

There should be no corruption unless you already have corruption on the data drives.    Parity will be built to correspond to whatever is already on those drives.

Should I format the 2nd 2TB drive in the array before replacing the parity drive so the corrupt data is not copied?

[JorgeB]

4 minutes ago, Theldron said:

How would I go about doing a re-sync?

-Tools -> New Config -> Retain current configuration: All -> Apply

-Assign old disk2 as disk2

-Assign new parity

-Start array to begin parity sync

 

Note: Any data written to disk2 after the upgrade will be lost

[Theldron]

Just now, johnnie.black said:

-Tools -> New Config -> Retain current configuration: All -> Apply

-Assign old disk2 as disk2

-Assign new parity

-Start array to begin parity sync

 

Note: Any data written to disk2 after the upgrade will be lost

Right sorry I am very new with Unraid, please bare with me.  So I would assign the old 1TB drive replacing the new 2TB drive that I put in yesterday. Assign the new parity drive and let the parity sync to the new parity drive.  Then when that is done, I could replace the 1TB with the new 2TB in the array?  Is that right?

[JorgeB]

5 minutes ago, Theldron said:

Is that right?

Yep.

[Theldron]

7 minutes ago, johnnie.black said:

Yep.

Thanks mate.

 

17 minutes ago, johnnie.black said:

-Tools -> New Config -> Retain current configuration: All -> Apply

-Assign old disk2 as disk2

-Assign new parity

-Start array to begin parity sync

 

Note: Any data written to disk2 after the upgrade will be lost

Sorry I know I am a pain. Would I retain current configuration before I unassigned the new array 2TB disk and replaced it with the old 1TB or after?

 

So I would unassign the parity drive and new 2tb drive - retain current config - power down, replace parity drive and put in old 1tb drive - power up assign 1TB drive to disk2 - assign parity start array?

 

Sorry again.

[JorgeB]

3 minutes ago, Theldron said:

So I would unassign the parity drive and new 2tb drive - retain current config - power down,

No, power down, disconnect old parity and new disk2, connect new parity and old disk2, array won't start because some disks will be missing, ignore, follow steps above.

[Theldron]

So I wouldn't unaasign them just pull them?

[JorgeB]

Yes, no need to unassign before the new config.

[Theldron]

13 minutes ago, johnnie.black said:

Yes, no need to unassign before the new config.

So pull disks and replace - power up - new config - assign old as disk2 - assign new parity - start array, think I got it  .  You are a star much appreciated.

[Theldron]

Sorry just had a thought. I don't know how long it will take for the new 2TB drive to come with all the delays in deliveries etc.

 

So the new 2TB (current disk2) i have has already been precleared and confirmed OK. Could I reuse that after I pull it as the new parity drive and use the 1TB in the array until my new 2TB comes and then replace that for the 1TB drive?

[JorgeB]

5 minutes ago, Theldron said:

Could I reuse that after I pull it as the new parity drive and use the 1TB in the array until my new 2TB comes and then replace that for the 1TB drive?

Yes.

[Theldron]

Everything seems to be working perfectly, the parity is rebuilding. Thanks for all your help.