How Duplicati handles hardware failures (unmounted vmount points)

First off, kudos to the entire team - love your work!

I have looked through the forums but couldn’t see an answer, so apologies in advance if it’s been answered before.

I have a Ubuntu box with about 1.5TB of data that I backup to a BackBlaze B2 bucket. Awesome.

Now, say the external hdd that the data is currently on (zfs partition mounted at /mnt/z) suddenly dies, or for whatever reason, power is lost and the drive fails to mount at startup…

Question: will Duplicati start up, scan /mnt/z, think it’s empty and then backup the “empty” folder? Or, will it detect (if so, how) that something is wrong and put a halt on things?

What if another program or script blindly wrote a file, say /mnt/z/log.txt - would Duplicati think that I’ve decided to replace all my family photos with a single text file and upload that?

For now I have versioning turned on, which I know will probably save my bacon in the worst case scenario, but I’d like to know others thoughts.

I would simply try it myself but I’d really like to avoid the painful 1.5TB upload process again if at all possible!