Just upgraded main server, have 8 disks laying around to put in a second (backup) server.  They were used in previous unraid installations.

 

When I boot unraid and start the array, it recognizes all of the info on the disks and wants to rebuild parity.  

 

I installed the preclear disk plugin, and even when I have no drives assigned, it says "no unassigned drives found."  So I can't preclear the drives.

 

All I want to do is format all 8 disks and start from scratch with a brand new server, devoid of all data.  What is the easiest way to accomplish this?

 

Thanks.

That is expected behaviour as you are not allowed to preclear disks already assigned to the array (you said you HAD assigned the drives to the array).   If you really want to preclear them then Go to Tools->New Config to reset the array.  The disks will now show in Unassigned Devices so they can be precleared.   After preclear completes then assign them to the array.

 

Alternatively if you trust the disks you can skip the preclear process and save a lot of time.   In this case stop the array; change the disk format; restart the array; select the option to format the disks.  The format should only take a few minutes.   If the result is not the format you want end up with repeat the process and this time set the format you want to end up with. 

 

In in both cases you will have to do an initial build of parity, but the array is useable while this takes place

 

 

Thanks, I'll try the format thing.  I've run "new config" a dozen times now and nothing happens.

Stop your array and for each disk change the file-system format. To force a "format disk action" you'll need to change the file-system format to something different.

 

Once done for all diks, start the array and allow it to do a format action on the disks. If this is not your "final" filesystem format. You will need to stop the array again after the formatting of all disks is completed. And redo the above action by setting the "correct" file-system format.