Raspberry Pi Network Monitor: Watch Every Device on Your Network 24/7

A Raspberry Pi is the perfect network monitor. It's small, quiet, uses a few watts, and it's on all the time, which your laptop and your phone are not. In this video we turn a Pi into a monitor that watches every device on the network around the clock, and tells you when something joins, leaves or breaks.

The software is DeviceShelf Server. It scans the network every few minutes, keeps the history, and shows everything in a dashboard you open in the browser. We'll install it first, then walk through what it shows.

You need a Raspberry Pi 4 or 5 with the sixty four bit version of Raspberry Pi OS. DeviceShelf Server comes as an image for sixty four bit ARM, so a Pi with a thirty two bit system won't do. Connect the Pi to the router with a cable if you can. Wi-Fi works, but a cable is steadier, and the Pi has to sit in the network it watches.

The easiest way to run it is Docker. If the Pi doesn't have it yet, Docker's own install script sets it up in one line. The second command lets your user run Docker without typing sudo every time. Log out and back in after that.

Make a folder for DeviceShelf with a data folder inside. The server runs as an ordinary user with the number ten thousand and one, not as root, so that user gets the data folder. Then create a file called docker dash compose dot yml.

This is the whole file, as on the DeviceShelf server page. Network mode host is the important line: it puts the server directly on your network, so it can see every device. The two capabilities allow the network scan and the listening for devices that ask the router for an address. Restart unless stopped brings it back after every reboot.

Start it with docker compose up. The first scan begins right away. The last command prints the access token and a login link with the Pi's address and port eight thousand and eighty eight. Open that link in the browser on any computer at home, and you're in.

And this is what you get. What you see now is DeviceShelf's demo network, a made-up home with forty six devices, so no real addresses. On your Pi, the same dashboard fills with your own network after the first scan.

The top row shows how many devices are online and tracked, the network the Pi watches, and when it last scanned. By default that's every five minutes.

The rankings point out the devices worth a look: the worst availability, the longest outages, and the most events. That last one is often a phone or laptop that keeps coming and going.

The timeline is the Pi's diary of your network. A device joined, one went offline, one came back, a new port opened. Each entry has a time, so you can match it to what happened at home.

Click any device for its details. Fittingly, here's a Raspberry Pi in the demo network. You get its addresses, vendor, open ports, and its history of availability and response times.

The Security view checks every device for open ports that shouldn't be open and for software with known vulnerabilities. The Pi in the demo still has Telnet open, and its SSH version has a known vulnerability. On your own Pi: switch Telnet off and keep the system updated.

Because the Pi is always on, it can tell you things as they happen. Under Settings, Alerts and notifications, pick what you care about: an unknown device joining, a device going offline, a new open port.

Then add a channel. ntfy is a good start: a free push app, no account needed, just a topic name. Pushover, Telegram, Discord and e-mail work too.

If the Pi already runs other things in Docker, like Pi-hole or Home Assistant, the server can watch those containers too. Mount the Docker socket read-only, and the Infrastructure view lists every container and warns you when one stops or keeps restarting.

And after a few weeks, Reports shows uptime for every device and every internet outage, with dates and durations. That's the moment a small Pi pays for itself. And over months, the same reports show slow changes too, like a device that drops out more often than it used to.

To sum up: take a Pi 4 or 5 with sixty four bit Raspberry Pi OS, install Docker, save the compose file, and start it. The dashboard on port eight thousand and eighty eight shows every device, its history and what changed, and alerts reach your phone. The compose file and the full guide are linked in the description.