Forum KNX francophone / English KNX forum

Version complète : KNX Kit - Problem in Detecting KNX interface
Vous consultez actuellement la version basse qualité d’un document. Voir la version complète avec le bon formatage.

I bought a KNX kit for training purposes from Ivory Egg and I got stuck with connecting ETS 5 to Gira router. ETS 5 cannot detect the interface no matter what I used to connect. I tried ping using network router in the middle and it replies but ETS cannot find it. It says No knx interface or something like that. Gira router is 2167 00. Please help!

Have you assigned the fixed IP to the Gira router ?

We need more informations (printscreen, schematics, ....) to help you.
I didn't fix the IP for Gira. I let it dynamic. Is there any issue in this? Also, I made no group addresses of the components as the Gira doesn't work probably. Does this effect? I will make printscreens and schematics attachments later when I get to my lab.

Many thanks for your help.
The first thing is to assign a fixed IP (outside the DHCP range).
After that you have to give the router a 'second' KNX physical address that will be reserved for the communication between the 2 networks (IP / KNX). This second physical address MUST be free and different than the physical address of the router in ETS.
Generally all the IP interface need 2 different physical address : one for the local connection and the second for the bus interface.

All these steps can be made under ETS5 (Bus page .... then interface on the left side of the window ... select your gira IP in the interface found list .... properties on the right of the window)

When you will give the second physical address, keep in mind that if your IP interface is able to have multiple IP connection, it will use a physical address for each connection.
For example if you set the physical address as 1.1.200, the first IP connection will use this adress, the second IP connection will use the physical adress 1.1.201, the third 1.1.202 .... ect
This is why I use the end of the range for the IP interface. ex : 1.1.250 for 5 connection IP interface (250 to 254)
Thanks pollux06 for your efforts.

I was quite busy with my exams so I did not follow up with KNX issue. Please excuse me for the late response.

I tried to follow your instructions but I did not get any results. Now I made some screen shots that shows the issue.

As you may see the KNX interface is not found per ETS although ETS knows it is in programming mode and identifies its MAC address. MAC address on the other hand is not captured in Properties in the devices pane!

Regarding schematics, I am now trying make communications with the router only present.

Can you please clarify this issue?

It's normal as you don't have the same network scheme between your interface and the Gira Tongue

On your first printscreen we can see that your computer is on the ip range and your Gira is on range.

If you want to communicate between your computer and the Gira they MUST be on the same IP segment. I don't understand why your DHCP server have assigned this IP ( to the Gira interface.

First check your DHCP server to see the assigned range (the first 3 numbers must be the same than the IP address of your computer). If the Gira does not ask for an IP to the DHCP, you will have to modify the IP of your computer (for example to access the Gira and then modify his parameters.

The best thing is to assign a fixed IP to the Gira outside your DHCP range but with the same scheme (3 first numbers) than all the other components of your private network.
Generally we use the scheme (or for a private network. With this scheme you can assign from to to any components of your network with no duplicate.

Once the Gira and your computer will be on the same IP address segment they will communicate together.
Thanks pollux6.

Well they are in the same segment. They were in 10.x.x.x network. I did that to make it in other segment than my wireless network. I worked your advice and configured my DHCP to assign addresses in the range 192.168.0.x. 224.x.x.x is the multicast and is shown there with no configuration from my side. It tests ok for the card or the called IP routing by ETS.

After I made changes to IP addresses it still not ok when tested by ETS although it shows the MAC address of the router and the status of the LED. There is something in configuration that I am missing but I do not know what it is!!

Once again thanks pollux6.
I ve added a rule in the firewall for the port 3671 further disabled the firewall but still no use. Also upgraded ETS to the latest version. The interface is still detectable by means of IP and MAC but not ok in Test!!
Can you make a printscreen of the bus windows ?

Just to check that the Gira interface is now in the range.

Justr have a look on the printscreen of my bus windows with 3 IP/KNX interface.
Here it is ..

Thanks for help. I see you have tunnel or tunneling in in the mentioned discovered interfaces in your bus page!
Does your Gira answser to a ping ?

And what happens if you open the gira web page with your brownser ( ?
Firefox: "Unable to connect

Firefox can't establish a connection to the server at"

Edge: "Hmm, we can't reach this page.

Try this
•Make sure you’ve got the right web address:"

Ping: "
Pinging with 32 bytes of data:
Reply from bytes=32 time<1ms TTL=64
Reply from bytes=32 time<1ms TTL=64
Reply from bytes=32 time<1ms TTL=64
Reply from bytes=32 time<1ms TTL=64

Ping statistics for
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 0ms, Average = 0ms
I even tried telnet to port 3671 which terminates immediately.
Here is a snapshot of wire shark sniffing data. Port 3671 works fine on gira!!

ok ... can you describe the physical connection (computer --> cross/straight cable ? --> switch (brand / model) ? --> cable type again --> ...............)

I've had once the same problem with a bad connection due to a gigabit switch. I've solved the problem by adding an old 10/100 switch (4 ports) between the gigabit switch and the IP/KNX interface. Don't forget that all the IP/KNX interface works at 10 Mb/s maximum and very often at 1Mb/s
On this old swich, I've connected my three IP/KNX interface and now everything works fine (more than one year)
computer --> crossover cable --> knx router

I installed dhcp server on the ethernet interface. And I made connections in earlier time through cisco router 2611xm with no good .. i made port forwarding setting. I do have an old hub and a cisco mediator that I ve never used.

One observation is that ETS reads device info, unload configuration, sometimes monitor bus shows activity.

Anyhow, I will try the old hub. I will try also the mediator. Slow connection information is totally new for me thanks for that and thanks for all.

I believe knx in need for thorough learning resources in English.

I also tried a switch but i believe it's new i.e. gigabit ethernet with no good!
Try the following connection :
computer --> straight cable --> old switch --> straight cable --> Gira router
Computer --> straight cable --> Gira router

Just let the DHCP server on your ethernet interface and erase every port forwarding