I found that Hirschmann switches RS20 have an interoperability issue with our Emerson DeltaV controller SX/SD+ .when the switches and the redundancy controllers are power-cycled at the same time, there are no communication at all, the switches port lights are solid green, we find a "red cross" in DeltaV Exploer,but the CIOC cards which connected the same switch can be commisioned, the switch is RS20-0800S2S2TDHEHH and version is L2E-04.0.01. any expert can help me to resolve the issue, the Deltav version is 11.3.1, the issues only occured when both of them are power-cycled ,power-cycle each of them haven't affected the commisioning.
In reply to BobHuba:
I got support from GSC, the technical expert also suggest me to degrade the versiion of RS20, I think this is the only way i can do.thanks, Bob.