Well my day job is managing Linux systems so it was no brainer, I run other workload on the NAS too, not just file shares, and doing that on off the shelf NAS would just be a PITA.
Wow consumer ITX boards are expensive, rather limited, and look like they will suck power too.
The what now?
Personally I'd buy big power supply at the voltage it needs, get some board with fuses and connect all to that.
But it seems you need few more shelves and pack of zip-ties first.
Well, yeah but you want to know which one burns the slowest
Flash is... not great for cold storage from what I've read. Electrons eventually leak out and your data is gone. Well, unless you put it in freezer
Fun fact: JEDEC specification for commerical flash only specifies year of retention as minimum at 30C and much lower at elevated temperature
https://www.seagate.com/files/staticfiles/docs/pdf/whitepaper/tp618-ssd-tech-paper-us.pdf
Which header you're using? I had bad luck with readers being pretty wonky.
Would be interested in results, my SBC cluster died on a bunch of samsung EVO cards turning read-only.
Or rather PRETENDING to be read-write by ignoring writes, which made very funny debugging session where the OS started crashing the moment write cache in RAM ran out and it tried to read the data it wrote...
I've been meaning to try Zitatel which apparently have unique feature of being able to act as LDAP server, that might be one option