# Laggy KNX-Switches and offline KNX-Things

**URL:** <https://community.openhab.org/t/laggy-knx-switches-and-offline-knx-things/134632>\
**Category:** Beginners\
**Created:** [March 29, 2022, 9:40am UTC](https://community.openhab.org/t/laggy-knx-switches-and-offline-knx-things/134632 "2022-03-29T09:40:12Z")\
**Posts on this page:** 7\
**Page:** 1

<div class="post-metadata">

**Author:** ![Cyberseppi](https://community.openhab.org/letter_avatar_proxy/v4/letter/c/91b2a8/32.png) [@Cyberseppi](https://community.openhab.org/u/Cyberseppi)\
**Post date:** [March 29, 2022, 9:40am UTC](https://community.openhab.org/t/laggy-knx-switches-and-offline-knx-things/134632/1 "2022-03-29T09:40:12Z")

</div>

Hi there,

I´m just trying to migrate from openhab 2 and legacy knx to the new world.

I have this config:

Host: Ubuntu VM (for testing → later raspberry)  
openHab Instance: Docker

I reduced the config here for better readability

knx.things

```auto
Bridge knx:ip:bridge [
    type="ROUTER",
    ipAddress="224.0.23.12",
    portNumber=3671,
    //localIp="192.168.0.11",
    readingPause=50,
    responseTimeout=10,
    readRetriesLimit=3,
    autoReconnectPeriod=60,
    localSourceAddr="0.0.0"
]{
    Thing device Aktor_1_1_1 "Aktor_1.1.1" [
    address="1.1.1",
    fetch=false,
    pingInterval=600,
    readInterval=0
    ]
    {
                Type switch : ch1 "Erdgeschoss Kueche" [ga="1/1/0+5/1/12"]
                Type switch : ch3 "Erdgeschoss Esszimmer" [ga="1/1/4+5/1/13"]
                Type switch : ch2 "Erdgeschoss Wohnzimmer" [ga="1/1/6+5/1/14"]
                Type switch : ch6 "Erdgeschoss Buero" [ga="1/1/13+5/1/16"]
                Type switch : ch8 "Erdgeschoss Speiss" [ga="1/1/9+5/1/17"]
        
    }
            Thing device Aktor_1_1_8 "Aktor_1.1.8" [
                address="1.1.8",
                fetch=false,
                pingInterval=600,
                readInterval=0
                ]
                {
                            Type dimmer : ch1 "Erdgeschoss Esszimmer" [switch="1/1/3+<5/1/4", position="2/1/9+<5/1/5", increaseDecrease="2/1/2"]
                            Type dimmer : ch2 "Obergeschoss Schlafzimmer" [switch="1/2/5+<5/2/1", position="2/2/6+<5/2/0", increaseDecrease="2/2/0"]
                    
                }
}

```

knx.items

```auto

Dimmer Erdgeschoss_EsszimmerEsstisch "Erdgeschoss_EsszimmerEsstisch" { channel="knx:device:bridge:Aktor_1_1_8:ch1" }
Switch Erdgeschoss_BueroDeckenlampe "Erdgeschoss_BueroDeckenlampe" { channel="knx:device:bridge:Aktor_1_1_1:ch6" }

```

Now, the switches, but sometimes with tremendous lag (15 secs)  
The dimmer doesn´t work at all (addresses are correct)

The channels are ALL offline, the gateway is online

 ![image](https://community-openhab-org.s3.dualstack.eu-central-1.amazonaws.com/original/3X/9/a/9a721626716115c923bebf1d9284a18d344d8beb.png)

Several questions:

- Where could the lag come from ? (it´s sporadic)
- Why doesn´t the dimmer work ?
- Why are all the channels offline ?
- What´s the best approach for analysis ?

Many thanks in advance guys!

Greetings,

Julian

---

<div class="post-metadata">

**Author:** ![Cyberseppi](https://community.openhab.org/letter_avatar_proxy/v4/letter/c/91b2a8/32.png) [@Cyberseppi](https://community.openhab.org/u/Cyberseppi)\
**Post date:** [March 29, 2022, 12:49pm UTC](https://community.openhab.org/t/laggy-knx-switches-and-offline-knx-things/134632/2 "2022-03-29T12:49:06Z")

</div>

I answered the question

- Why doesn´t the dimmer work ?  
myself.

The dpt were missing.

---

<div class="post-metadata">

**Author:** ![Cyberseppi](https://community.openhab.org/letter_avatar_proxy/v4/letter/c/91b2a8/32.png) [@Cyberseppi](https://community.openhab.org/u/Cyberseppi)\
**Post date:** [March 30, 2022, 8:57pm UTC](https://community.openhab.org/t/laggy-knx-switches-and-offline-knx-things/134632/3 "2022-03-30T20:57:02Z")

</div>

nobody ? ☹

---

<div class="post-metadata">

**Author:** ![Cyberseppi](https://community.openhab.org/letter_avatar_proxy/v4/letter/c/91b2a8/32.png) [@Cyberseppi](https://community.openhab.org/u/Cyberseppi)\
**Post date:** [April 3, 2022, 9:09am UTC](https://community.openhab.org/t/laggy-knx-switches-and-offline-knx-things/134632/4 "2022-04-03T09:09:58Z")

</div>

hmmmm… I´m on my own here, it seems ☹ …

Thanks for reading anyway guys …

---

<div class="post-metadata">

**Author:** ![rpwong](https://community.openhab.org/user_avatar/community.openhab.org/rpwong/32/36036_2.png) [@rpwong](https://community.openhab.org/u/rpwong)\
**Post date:** [April 6, 2022, 6:33pm UTC](https://community.openhab.org/t/laggy-knx-switches-and-offline-knx-things/134632/5 "2022-04-06T18:33:53Z")

</div>

Sorry you’re not getting a response. I don’t know anything about KNX, so can’t be of any help.

If it were me, I’d try to set it up from scratch, so that you don’t get stung by any config that doesn’t properly carry over from OH2.

It might help to change the title of the post so that it’s more obvious this is about KNX.

---

<div class="post-metadata">

**Author:** ![Cyberseppi](https://community.openhab.org/letter_avatar_proxy/v4/letter/c/91b2a8/32.png) [@Cyberseppi](https://community.openhab.org/u/Cyberseppi)\
**Post date:** [April 6, 2022, 8:07pm UTC](https://community.openhab.org/t/laggy-knx-switches-and-offline-knx-things/134632/6 "2022-04-06T20:07:14Z")

</div>

Now that you say it 🙂 … you´re perfectly right…  
I´ll change the title … 🙂  
Have a great evening ahead of you!

---

<div class="post-metadata">

**Author:** ![stamate\_viorel](https://community.openhab.org/letter_avatar_proxy/v4/letter/s/41988e/32.png) [@stamate\_viorel](https://community.openhab.org/u/stamate_viorel)\
**Post date:** [April 7, 2022, 6:31am UTC](https://community.openhab.org/t/laggy-knx-switches-and-offline-knx-things/134632/7 "2022-04-07T06:31:20Z")

</div>

```auto
Bridge knx:ip:bridge [
    type="ROUTER",
]{
    Thing device Aktor_1_1_1 "Aktor_1.1.1" [
    fetch=false,
    pingInterval=600,
    readInterval=400
    ]
    {
                Type switch : ch1 "Erdgeschoss Kueche" [ga="1/1/0+5/1/12"]
                Type switch : ch3 "Erdgeschoss Esszimmer" [ga="1/1/4+5/1/13"]
                Type switch : ch2 "Erdgeschoss Wohnzimmer" [ga="1/1/6+5/1/14"]
                Type switch : ch6 "Erdgeschoss Buero" [ga="1/1/13+5/1/16"]
                Type switch : ch8 "Erdgeschoss Speiss" [ga="1/1/9+5/1/17"]
        
    }
            Thing device Aktor_1_1_8 "Aktor_1.1.8" [
                fetch=false,
                pingInterval=600,
                readInterval=400
                ]
                {
                            Type dimmer : ch1 "Erdgeschoss Esszimmer" [switch="1/1/3+<5/1/4", position="2/1/9+<5/1/5", increaseDecrease="2/1/2"]
                            Type dimmer : ch2 "Obergeschoss Schlafzimmer" [switch="1/2/5+<5/2/1", position="2/2/6+<5/2/0", increaseDecrease="2/2/0"]
                    
                }
}

```

Try like this but keep in mind that the router needs multicasting to work so check with your router for igmp to be disabled also check the load on your bus and if the trafic is below 5 percent then try readInterval of the thing to lower it but preferably adjust the devices to send the value after each change