Crossover Redundancy

Dear Community Members,
I have a requirement from a customer. As shown below, there should be network redundancy for Northbound communication.


The cross over failure test will be preformed by removing one cable from the PLC and turning off the other PLC. i.e. w.r.t the above architecture removing primary network cable from the Primary PLC and turning off the Secondary PLC or turning off the primary network switch and turning off the secondary PLC. In both the scenarios there should be no data loss in the clients.
Is it possible? If yes, then how?

One option is to use Ethernet interface Bonding:
Automation Help: Bonding

And when using Controller Redundancy. If you use the Cluster address for connecting, it will most likely require a reconnection when the active plc is changed (so some data might be lost during the reconnection).

You can also directly connect to both the Primary and the Secondary at the same time separately by using their own addresses. This way there should be no data loss, but you will need to post process the data on the receiving end (which PLC is currently active).

2 Likes

Thanks Tommi,
it seems, your solution is working.