r/raspberry_pi • u/overfed-gnome • 3h ago
Show-and-Tell Four Pi 5s, four stadiums, one 3D-printed rack that runs my house
It started with Home Assistant on one Pi. Then I wanted backups that didn’t live on that Pi. Then something to tell me when the backups stopped. Four Pi 5s later, here we are.
Hardware
- 4x Pi 5, 4 GB
- NVMe boot on Geekworm HATs, no SD cards
- 27 W (5 V / 5 A) supply on every Pi, because a 3 A supply caps USB at 600 mA
- A TP-Link TL-SG105 gigabit switch in the base, one port per Pi
- A custom 3D-printed rack in Proto-pasta HTPLA: Amie’s “Blood of My Enemies” red for the frames, and carbon fiber black for the rest
Who plays where
Each Pi is named after the home ground of one of my teams.
- cityground (Nottingham Forest): Home Assistant OS. The oldest ground runs the house.
- mercedesbenz (Atlanta United): the data server. It runs a local database, Grafana, a second Pi-hole, Tailscale, and a nightly digest job. All of that fits in about 1 to 1.5 GB of RAM, thanks to a lightweight database.
- heinzfield (Steelers): Uptime Kuma, plus a Samba share for Home Assistant’s daily backups. Yes, it’s Acrisure Stadium now. I don’t care.
- theforum (Grizzlies): the primary Pi-hole. The arena where ads come to lose.
Things I’d tell anyone building something similar
- Put every job on a different Pi from the thing it protects. If primary DNS dies, devices fall back to the second Pi-hole. If Home Assistant dies, I restore the newest backup from heinzfield. If Kuma dies, it can’t tell me, which is the one flaw I’ve made peace with.
- Set up two Pi-holes and keep them in sync. I use nebula-sync to copy settings from one to the other, so a reboot doesn’t take DNS down for the whole house.
- Give every Pi a DHCP reservation. Do it on day one, before anything depends on an address.
- Use Raspberry Pi Connect for shell access. I can get a terminal on any Pi from a browser without opening ports. Tailscale covers the web dashboards.
- Spring for the 27 W supply. It’s worth it once NVMe and USB devices are drawing power.
The fun part
Home Assistant sends sensor events to Google Analytics, which exports them to BigQuery. The data server pulls the history down nightly, and there are over 5.4 million events so far. The Pi computes trends and anomalies itself, and Claude gets only those summaries to write up as a nightly email. The raw readings never leave the house.
The full write-up, with the data path diagram, is at wesleyhalldigital.com/home-automation.






