Hi, 

we have encountered same problem but with Nokia 7210 Router.

We have a system where a PLC (1512) and RIO are connected to a Layer 2 switch. When we connect this switch to router with a gateway (Nokia 7210 Mxp), we experience an issue where the PLC cannot access the IO after a restart (its enough to disconnect/connect Ethernet cable). The solution is to disconnect the gateway so that communication with the IO is restored, and then the gateway can be connected again.

Did you found any solution for your problem?

I appreciate every tips.

Greetings

Bartosz 

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Split from PLC Losing Connection to Profinet Devices.

We found solution.

It was necessary to disable “Local Proxy ARP” function.