I have several cnMatrix switches that are connected to each other with a 2 port LAG over PTP820c radio links using two smart pipes. I have matched the MTU (1538) on the cnMatrix to the MRU (1538) on the PTP820c radios. I am seeing “Received Errors” on the second LAG interface on the cnMatrix. I am also seeing “TX length error frame count” for the PTP820c Eth interface connected to the second LAG port on the Matrix. I am also seeing a lot of “RX length error frame count” on the PTP820 especially on the primary LAG interface. I have tried adjusting the MTU/MRU values with varying results, but I have never found a setting that does not generate the aforementioned results. These errors are causing dropped packets for customers whose traffic traverses the second LAG interfaces.
Does anyone have any ideas as to why this happens over a LAG? I have never seen these issues using a single interface and MC-ABC on the PTP820c radios.