It really depends how you define reliability. SD cards are physically nigh indestructible, but can show failure when overwritten often. Hence for one off backups it’s actually a good alternative. It will start showing problems when used as a medium that often writes and overwrites the same data often.
I would recommend backups on SD cards in an A/B fashion when you want to give a backup to someone else to store safely.
Back in the day I bought a fridge freezer combo, second hand, no handles. Used to be a built in model. As handles I used two magnets from full height drives, they were ludicrously strong and shaped like a little bit like a handle.
Full height drives were 3.25" high for those who are wondering.
One logs into the VM and starts checking the files of course. Go from there.
Curious, you might want to look into what’s generating your data first. It’s easy to generate data, it’s harder to only keep the data that’s useful.
Curious, you might want to look into what is generating your data then first. It’s very easy to generate data, it’s a lot harder to only generate and keep useful data.
Consider running HA in a light weight systemd-nspawn container with minimal debian. No docker, only install the repositories you need. HACS if needed. Run your own database on the side somewhere and let HA use it.
By itself HA is fairly lightweight already.
Adding to that that you can also easily make a separate WiFi network (tied to a vlan even) for IoT. OpenWRT makes this very easy.