I got intouch with OWC support and they confirmed my suspicion that the data from the volume is likely not recoverable. However, the drives seem perfectly healthy.
According to the log both drives failed at exactly the same moment. That seems to be a good indication this was a software issue perhaps very similar to what @aaronneitz had experienced in the past.
I rebuilt the volume using raid0 this time and we are off and running.
Thanks everyone for responding and sharing your thoughts.
Could OpenZFS be installed on a Mac and used with the Thunderblade? Or would ZFS soak up too much RAM?
We just purchased one of these, and just now I am seeing how many problems people are having with the Thunderblades.
One of the many lovely things about zfs is how resilient it is.
If for example you buy a bucket load of 2.5" ssd that don’t draw tons of power, don’t get too hot, max out at 500MB/s…
And if you can find a large enough SAS/SATA backplane that works with your platform…
And if you can find a SAS pass through card that works on your platform…
You can build a simple MIRRORED RAID that will most likely last you well over five years…
And if you can get your self a PCIe card that can host a few NVMe chewing gum sticks then you’re off to the races:
Use the NVMe as an L2ARC and you get all the glory of RAID whatever you want, and if it fails, you just remove it, carry on with the storage that you have, and replace the NVMe when you can.
It’s like a turbo on an engine - take it off and the engine still runs, albeit a bit slower.
openZFS is an extraordinarily valiant effort at maintaining a fundamentally brilliant concept.
oracle zfs is so powerful when coupled with oracledb that Larry Ellison just spoke some words that you might want to grok.