I’m currently setting up a KNX integration with Home Assistant, but I’m running into an issue when controlling a light.
Problem
When I toggle a light entity in Home Assistant, there is no effect on the physical KNX device.
However, I can see the telegrams arriving in ETS, so HA is definitely sending something.
Setup
My topology looks like this: Home Assistant → MDT KNX IP Interface → GIRA RF Mediacoupler → GIRA RF Switch
The RF switch is configured as both:
actuator (output)
sensor (input)
ETS Configuration
I created a group address for the light
Assigned it twice on the GIRA RF device:
once as output (actuator)
once as input (sensor)
When I physically press the button, everything works as expected: Wwitching works and status updates correctly
Hi !
Your group address is set up as DataSecure (see the blue lock icon ). You'll need to assign the GA to the tunnel HA is using and export the Keyring for HA. See Knx integration documentation paragraph "Knx Connection".
Or you disable DataSecure for that GA.
Be aware that your MDT interface has had (maybe still has, don't know if they ever fixed that) a bug in providing correct secure tunnel endpoints, so you might need to assign all its tunnel endpoints with the secure GA(s) you want to use with HA.
Independent of RF, you don't need that, but it's good practice to do so, as the status can get queried (GroupValueRead) and you might not want the response to trigger things (eg. if there are locks involved or multiple devices associated).
Hi @farmio, thank you for your quick reply. Understood. I assigned the GA to the tunnel HA is using. I reuploaded the keyring for my interface connection. (This section: KNX - Home Assistant)
Just checked the group monitor. I receive the telegrams in ETS form HA as mentioned. Weirdly it says tunneling channel 2. That is the bad behaviour you mentioned in the second part of your answer right? (Although HA is definetly configure to use ch 1 and the physical address shown in HA is for ch 1...
I will assign all GAs I am using to all tunnels now.
You can only use one for HA. You'd need to assign the GAs to all Tunnels in ETS.
Yes. And every time you change anything with regards to that GA.
You don't need to update the project file or entity configuration though.
Right. MDT has an off-by-one error there since forever. It should only affect IP Secure connections. So you'd need to assign to the endpoint you want to use and the next. I think ... don't have such a device personally.
AFAIK if you select Tunnel 2 in HA you'll get Tunnel 3 from MDT.
Got it — I followed all the steps exactly as you described and suggested, but still no luck.
What I don’t fully understand is this: I can see the telegrams in ETS, which means Home Assistant is definitely sending them and the interface is receiving them. So somewhere along the line, things seem to break.
Is it possible that the interface is not forwarding the telegrams to the actuator? Or that the actuator doesn’t interpret them correctly?
Do you think the issue could still be related to the KNX ↔ Home Assistant configuration?
Writing values within ETS6 gives me these results:
If a device receives a non-secure telegram it will be discarded.
If a device receives a secure telegram it checks against an internal table of possible senders. If sender is not in that table it's discarded. This table is updated by ETS -> hence the interface association and reprogramming of all involved devices after every change (a bit like coupler filter tables).
ETS will not send secure telegrams directly - since it isn't in any of those tables. And if it would just use some devices IA, the secure sequence numbers would get messed up. Therefore it tells some other device that is associated to send on its behalf -> that's the communication pattern you observed there.
!
). You'll need to assign the GA to the tunnel HA is using and export the Keyring for HA. See Knx integration documentation paragraph "Knx Connection".
