LM COEXISTENCE

[Frank68]

Greetings

on a system the customer asked me if it was possible to have two LMs with the same project so that in the event of one failure everything would continue to work.

Is it possible to have 2 with the same project with locally different addresses but which then ultimately supervise the same system, considering that there are scripts on the 2 LMs that could conflict or generate anomalous traffic on the BUS?

A thousand thanks

[Daniel]

Yes, you can make a watchdog where one LM keeps sending a telegram to other and if no telegram then you enable all scripts on another LM. Make sure not to make KNX loop, the simplest option is to change knx multicast on one of them.

[Frank68]

Yes, you can make a watchdog where one LM keeps sending a telegram to other and if no telegram then you enable all scripts on another LM. Make sure not to make KNX loop, the simplest option is to change knx multicast on one of them.

Hi

how do I create the watch dog and how do I use it, an example?

A thousand thanks

[Daniel]

Something like this would do
https://openrb.com/master-slave-logicmachine/

[Thomas]

Actually this is a prety complex task. I don't understand why there's no direct support from LM there. You have to do following:
- Users and access rights synchronisation
- Schedulers disabling and synchronisation
- scenes disabling and synchonisation
- Disable all scripts on backup LM that may affect your KNX object state if it's not active
- Disable Modbus IP readings if your device access is limited to one session only.
- swap IP addresses (or use a load balancer instead of direct access)