That's a brilliant setup — mutual offsite backup with parents. I love that you help them with Pi-hole + security and get offsite in return, everyone wins. Way better than my lonely USB in the same closet. For heat your split is smart too — low power always-on for photos and heavy stuff only spins up when accessed. I might steal the parents idea, my mom has fiber and would benefit from Pi-hole anyway. Thanks for sharing!

Thanks, solid points. AC — you are right, but the heat is only in the closet, not bedroom. Closet door is usually closed, bedroom itself is fine. AC for the closet would be overkill, I just vented it. Downclock — already did, BIOS limit 35W and -50mV undervolt, plus ML only 02:00-06:00. That dropped 8-10C and it's still enough for Immich. Monitoring — good call. Right now I have simple cron + healthchecks.io ping that emails me if backup is older than 2 days. LGM (Loki, Grafana, Mimir) is great but feels heavy for one Optiplex in a closet. I'm looking at Uptime Kuma with email to wife + me if backup job fails — simple dashboard she can actually open. "Document everything in case you die" — 100% agree, this is my current task. Writing a 1-page README for wife: where files are, how to get plain JPGs from Immich without Docker, B2 credentials in Bitwarden. That's more important than any stack. Appreciate the checklist.

You are right, it should be automatic — and now it is, but in January it wasn't. My mistake in January: I had Immich running and thought "I have a copy on the Optiplex, so it's backed up". It wasn't. No 3-2-1, just one HDD. Now it's automatic and boring, which is what I wanted: Daily: Immich DB dump + rclone sync to external USB (kept in same closet but different disk). Weekly: rclone sync encrypted to B2 — about $6/mo vs $15+ for Google One family. Monthly: I test restore of one random photo from B2, just to be sure. It's 2 cron jobs in Proxmox host, not inside LXC, so it runs even if LXC is down. Took 30 min to set up once. Heat is harder, yes. My fixes that actually helped: BIOS power limit to 35W, undervolt -50mV — temps down 8-10C, still fine for Immich. Immich machine learning (face recognition) only runs 02:00-06:00 via cron, not all day. Cut a small vent at top of closet door + USB fan pulling air out, wife stopped complaining. Happy to share docker-compose if you want — it's just Immich + Nextcloud + postgres + redis, nothing fancy.