How to make a new UnRAID with existing data and parity drives?

[Printingdude]

I'm curious to know if there's a straightforward way to take an UnRaid 4.5.6 array of disks, and create a new UnRaid USB stick (of any version) that I can configure to work with the existing Parity and Data drives from that UnRAID 4.5.6 system (retaining the data on the disks being the key concept).  I previously wrote about my UnRaid hanging at boot at bzroot, and I created an entirely new UnRAID system and was copying data to it one drive at a time using the unassigned devices extension.  Then I had my new UnRaid get hit with a ransomware attack while one drive from the old UnRaid was still connected to the new UnRaid.  My idea is if I can somehow get my old 4.5.6 UnRaid functioning with a new USB stick of any version of UnRaid, I could use it to reconstruct the one drive that got hit in the ransomware attack.

Is this something that can be done?

[pwm]

If you have a valid license for the required number of disks, then you can copy configuration from another USB stick. It's specifically the file "super.dat" that contains the list of which disks that belongs to the array and what position they had in the array.

 

But since the license is bound to the USB stick and not to the machine, you could use your current USB stick in the old machine if you make a backup copy of the configuration files for the new machine and then transfer the configuration files for the old machine.

[Printingdude]

I do have a valid license for the stick that is in the old UnRaid.  (I have a 2-pack, so I have two licenses for more disks than I'll ever actually need.)  So my new UnRaid is running on its own license.

Follow-up question:  Will the "super.dat" file work in any other version of UnRaid other than the 4.5.6 version it is in?
I do not mind re-imaging my USB stick, because it hangs at boot anyway.  I'd love to put a newer version of UnRaid on it if the old "super.dat" file will work with it, but it isn't clear to me if that would work or not.

 

[pwm]

If you have a licensed USB stick for the old machine - where the corrupted disk comes from - then I don't see a need for any additional work. The old system should already have all it needs to be able to rebuild the missing content onto a new disk.

 

But there is one potentially big issue. When taking drives from one unRAID and mounting in another machine, you invalidate the parity of the unRAID system unless the drive is mounted read-only. And that means that the old machine in that case will not have valid parity - which directly affects the ability to rebuild a missing disk without introducing corruption on that disk.