KNX Gateway lose connection but Openhab says it's online

Hi all,

Since few months ago I have strange malfunction with the KNX binding. Frequently all KNX devices can not be actioned via Openhab. After a deep investigation I have seen that KNX Gateway in openhab says its online, but if I look into the KNX Gateway web page I can see that the link has been lost.

I don’t know how the binding manage the gateway connection or reconnection but it’s strange that openhab doesn’t seems to know that the connections has been lost with the gateway. I’ve also checked the logs but there is nothing “strange”. Sometimes it happens just once in a week, other times it happens more than one per day and the only way to resolve it is to restart the system.

Anyone has this same issue? Do you know how to solve it?

Here is my configuration of the Gateway:

UID: knx:ip:ae1118bf
label: KNX/IP Gateway
thingTypeUID: knx:ip
useNAT: false
readRetriesLimit: 5
autoReconnectPeriod: 60
localSourceAddr: 1.1.200
readingPause: 50
type: TUNNEL
portNumber: 3671
responseTimeout: 20
location: Panel Domotica

Thank you very much,
Kind regards,

I think “Online” in OH means your gateway is reachable, but not that the gateway is connecting properly to the knx bus, but I may be wrong on this.
My impression is that the issue is happening on the knx side - maybe there is something fishy going on in the gateway or one the bus as the gateway itself reports on the connection loss in its UI, which leads to this assumption. Did you try to powercyle the gateway device (BTW:which one are you using ?) to reboot it? Did you add new device to the bus ? Then maybe you exceeded some limits causing the bus to become unstable.
There may be multiple reasons for this behaviour.
Do you have a second interface in place so you could check with it?

And please set the localSouceAddr to 0.0.0

Hi Oggerschummer,

I’ve set the localSourceAddr to 0.0.0 but it still lose connection. I’ve an IPAS ComBridge NCI. I will try to do a powercycle to the gateway to know if it solves it.

About new devices on the bus, few months ago I added two new actuators but the bus doesn’t seems to be unstable.

Thank you for your help.

Hi again.

I’ve rebooted the gateway. But now I think it could be something related with openhab. Let me explain why.

Before writing my previous message I tried to turn on a light with no result (this is how I know that the gateway connections has been lost). Then after reboot the connections between openhab and the gateway it was still lost, so I decided to reboot the raspberry.

In this moment something weird happened wile the system was shooting down. The light turned on. As in KNX a telegram can not be waiting in the bus i suppose that openhab let this command in “stand by” and it could be the reason of lost connection. In this case it could be something related with the binding, but I’m not sure.

If someone have any idea I will appreciate it.

Thanks for your help