hansolo77

I appreciate your feedback.  Unfortunately there's not anything I can do about the power.  The setup of my server uses 2x server grade PSU's that combine into a PDU.  That PDU only has so many cables on it.  In fact (and you may feel like this is an ah-ha! moment) I had to use a splitter to get 2 SATA power connector's out of one.  I've previously connected various drives (2x8tb, then 2x12tb, and now 2x20tb) to this primary cable.  Also, although not mentioned, I have tried switching cables (first to a 4-pin MOLEX splitter with 4 in and 4 out, and then to a SATA splitter with 4 in and SATA out) but had no change in behavior.  This has definitely been an eye-opening experience for me.  I've been building computers since the 90's.  I pretty much know everything on the hardware-side to try.  I even at one point tried having the drives OUTSIDE the case, just in case the problem was something possibly "magnetic" because they're mounted on the side of the power supply (see the pictures in my build).  At this point I don't think it's hardware.  
 
I take that back though.  It looks more and more like the problem is with Ryzen and Linux.  I made a post (mentioned in the OP of this thread) on the motherboard's manufacturing forum about the issue I'm having.  The general consensus was to upgrade the BIOS.  I did that, then started to rebuild parity again.  It made no difference at all.  I still ended up getting hard and soft resets (although the drives never disabled).  My last ditch effort was to install a separate SATA controller.  With it connected, I've not had ANY further reset issues.  I started a parity check last night and noticed it having errors so I'm rebuilding a clean parity now using the new controller (the last parity was built on the motherboard controller with drives resetting, so hopefully this will solve everything).

I'm going to mark this as resolved.  I had another 100% successful (without error) parity check and the logs have been clean.  I definitely feel at this point that the problem was with the SATA connector.  Had a crack in it, so it was apparently keeping the connection loose.  If things change, I'll try to remember to reopen this thread.  Thanks for being a support!

I saved it!
 
So I did some GOOGLE'ing and reading.  Somebody mentioned in another thread that the libvert.img stores the xml for the VM.  Since I hadn't rebooted, the VM itself was still on the drive.  I just needed to rebuild the VM's XML.  So, I took the libvert.img to my other computer and tried to open it up with no success.  WinRAR and Windows both said the file was corrupted.  BUT, the other thread user said he used Notepad++.  So I figured I'd TRY it.  Turns out, Notepad++, while showing a lot of JUNK binary data, DID manage to open the file.  For me, (instead of line 1500 like the previous user) my domain entry started around 4500.  I copied from <domain> to </domain> and pasted it into a a new VM using the custom template.  It failed to start, something about missing a file or something.  I edited the VM and just clicked the UPDATE button at the bottom.  Maybe there was some missing pathway or something.  All I know is, after I did that, the VM loaded right up and all my stuff is still there!  So, thanks whoever it was that had a somewhat similar issue and gave me an idea of something to try.
 
Love UnRaid!
 
EDIT:
Here's the thread and post that was most helpful to me...