Setup guide
Sentinel runs on a Raspberry Pi you can buy anywhere. Pick the board, pick a card, flash the image, boot it once at home — then it lives in your car and you stop thinking about it. Everything you need is on this page, in order.
Two boards run Sentinel. Both plug into the car’s dashcam USB port and behave exactly like the drive they replace — the car records straight onto them.
Pi 4 photo: Wikimedia Commons, CC BY-SAThe proven choice. Plenty of memory, plenty of headroom, and its USB-C port carries both power and data to the car in one cable.
Tiny enough to disappear into the glovebox, and costs about as much as lunch. Just as capable of being your car’s dashcam drive.
USBUSB — the outer PWR port is power-only and the car will see nothing. Data-capable cable here too.The Pi 5’s redesigned USB hardware (the RP1 chip) cannot act as a USB drive, so the car has nothing to record to. It’s a known platform limitation, still open — see bookworm-feedback #77 and raspberrypi/linux #6289. Buy a Pi 4 or a Zero 2 W instead.
Any card works — but endurance cards are built for exactly this: recording, all day, every day. They’re rated in years of continuous video where ordinary cards are rated in months. Three picks we trust:
The flagship — over a decade of continuous recording on paper. Set and forget.
The budget-friendly pick — still vastly outlasts regular cards, and goes up to 512 GB.
Samsung’s surveillance-grade line — the highest endurance rating of the three.
Sentinel splits the card into a camera buffer the car records into and a music partition for your tunes. Bigger card, bigger buffer — more hours of away-from-home driving survive on very long trips, until the car is back on your Wi-Fi and the footage comes home.
| Card size | Camera buffer | Music | |
|---|---|---|---|
| 256 GB | 64 GiB | 8 GiB | Minimum |
| 512 GB | 96 GiB | 16 GiB | Recommended |
| 1 TB | 128 GiB | 32 GiB | Recommended · long trips |
Going 1 TB? Endurance lines top out around 256–512 GB today — at that size, pick a quality standard card from a major brand.
Write the Sentinel image onto your card. Four tools, one result — use whichever you already know. If in doubt, pick Raspberry Pi Imager: it writes and verifies in one pass.
Use custom, then select the Sentinel image you downloaded. A compressed .img.xz is fine — Imager unpacks it for you.
Do this on your desk before the device ever sees the car. It takes about five minutes: join its setup network, enter your home Wi-Fi, and let it update itself.
Add a device, and enter the pairing code you wrote down. It lands in your Garage within a minute.Setup is done — the device already knows your home Wi-Fi. All that’s left is plugging it in.
After setup
In Storage, add your NAS, Dropbox or S3. The first destination becomes Priority 1; clips start flowing on the next parked Wi-Fi session.
Add a second network (a phone hotspot works well) under Wi-Fi. The device joins the highest-priority network it can find whenever the car parks.
That’s the point. The garage shows a green heartbeat and today’s offload count. If anything ever needs you, it turns red — and only then.