The internal drive in my legacy Tablo died yesterday.
I’ve learned my lesson. Since Tablo provides no backup mechanism, I’m going with an external RAID1 built from this: OWC Mercury Elite Pro Dual for Mac USB 3.1 Gen 1
That will at least remove each drive as a single point of failure. Yes, I know RAID1 isn’t strictly a backup, but I think it’s the best I can do in this case.
I like your idea. Never thought about that.
I would assume there is some legalities there for Tablo not giving us a backup option. Just my thought.
Nor do they provide a drive migration mechanism, where there are fewer legal ramifications - maybe?
While windows software cannot work with the EXTFS (linux based) file system on the Tablo Quad, Clonezilla produced a bootable USB disk for cloning hard drives. These steps were successful: 1) Purchased a 2TB Western Digitall SSD drive as a target disk. 2) Created a bootable USB disk using Clonezilla. 3) Removed the existing disk from my Tablo. 4) Disconnected all hard disks in my Intel based PC. 5) Photographed the back of both Tablo drives. (The existing disk is a 2TB Western Digital HDD). 6) Connected both disks to the onboard SATA contollers in my PC. 7) Booted to Clonezilla. 8) Selected disk-to-disk copy. 9) Referred to the photo to be certain I was selecting the right source and target disks. 10) Started the cloning process, which took about 8 hours. 11) Installed the new SSD drive in my Tablo and booted it up. I had zero issues. Tablo did not flag the new drive in any way. I had no prompts. It booted normally and began recording immediately. And, the old disk serves as a backup disk in case the new one fails. We had about 1.5 TB of data on the disk.
https://support.tablotv.com/hc/en-us/articles/213345486-Moving-your-recordings-to-a-new-Tablo
True (for legacy only), and I have done that successfully in the past. I would have had to anticipate the drive failure, however 
Again, true - for legacy only (but I would have had to anticipate the drive failure). This is not going to help 4th gen device owners, if others’ experimentation holds true. I’ve been told the 4th gen fingerprints the drive in some way that a cloned drive can’t match.