Supported recorders › Raspberry Pi
Raspberry Pi
The Raspberry Pi works as the KNXSENSE bus recorder through an external KNX/IP gateway.
How the recorder works.
The KNXSENSE recorder is installed on the Pi as a service of its own. It does not take the Pi over: the recorder runs in the background in its own separate environment, so the same Pi can keep doing other jobs alongside it.
The recorder reads the bus and never writes to it. It opens the connection outbound from the site, so no open ports, VPN or static IP address are needed. It also works behind a shared carrier IP address.
Recording requires the Raspberry Pi to be powered on continuously and the site to have an internet connection.
- Specifications
- Manufacturer
- Raspberry Pi Ltd
- Connection to the KNX bus
- External KNX/IP gateway
- Manufacturer’s product page
- raspberrypi.com →
- Operating system
- Raspberry Pi OS Lite (64-bit)
- Memory card
- microSD 8 GB or larger
(16 GB recommended) - Supply voltage
- Dedicated USB power supply
- Network interface
- Ethernet or Wi-Fi
(Zero 2 W Wi-Fi only) - ETS tunnel slots
- Only when tunnelling
KNXSENSE-compatible models
- Raspberry Pi 5
- Raspberry Pi 4
- Raspberry Pi 3
- Raspberry Pi Zero 2 W
Pi 5 and Pi 4 are the recommended choices.
How telegrams reach the recording.
The Raspberry Pi sees the bus traffic through the site’s KNX/IP gateways.
A single recorder reads up to 16 KNX/IP gateways at once and merges their traffic into a single recording. On a large site there may be, for example, one interface per line.
Telegrams never have to be routed from one line to another for recording, so traffic between the lines does not grow at all. If the same telegram is seen through two interfaces at the same time, it is recorded only once.
KNXSENSE compares the addresses it sees against your ETS project and tells you straight away which lines and devices are in the recording and which are missing.
KNX bus monitoring in your browser.
Every telegram the Raspberry Pi sees through the site’s KNX/IP gateways is recorded around the clock, to the millisecond, on our secure servers — even when you are not on site.
Telegram-level history reaches 400 days back on a rolling window. You can browse it in your browser, on any device, without the ETS software.
Remote ETS access through the interface, no VPN.
The connection is ETS tunnelling that runs through KNXSENSE. You open it in the user interface, and ETS then connects to the site’s KNX bus.
The recorder never takes the interface’s last free tunnel. If the slots run out, it releases its own slot and reconnects as soon as one frees up.
When the interface offers multicast routing, the recorder uses it and reserves no tunnel slots at all.
Remote access is included in the KNXSENSE monthly fee. No separate portal, licence, port forwarding or VPN is needed.
Setting up the Raspberry Pi as your recorder.
You write the memory card with Raspberry Pi Imager, connect the Pi to the network and run a single command containing a one-time install code. The Pi fetches the install package itself, verifies its integrity and uses the code to retrieve the site’s settings. Nothing else is needed.
- Import your ETS projectNames and structure from the project into KNXSENSE
- Write the memory cardRaspberry Pi Imager, settings ready
- Run a single commandA one-time code, and the Pi does the rest
- Recording is runningThe first telegram from the site’s bus confirms the connection
Setup is a one-off job. When updates to the recorder are released, they are installed on the Pi automatically. Updating requires no action from you and no visit to the site.
Other supported recorders.
You can run KNXSENSE bus recording on these devices too. Compare all →