having recently swapped 100tb of spinning media to ssd I am awaiting the first failures. now being a business environment it is all mirrored capacity. so I guess my question is from the article, are they running on a single device? No raid or mirror?

I am loathe to even keep my personal data at home on one drive and since I use an iMac that requires me to have time machine as mirroring/etc of the internal drive is not truly possible; at least I did not spend enough time researching it