HA interconnect alerts reported due a switch reboot

• ONTAP 9
• MetroCluster IP
• AFF-A400
• Back-end IP switches

• HA INTERCONNECT DOWN and MccIp_PortOfflineAlert reported on both nodes in one of the clusters
• sysconfig -a output shows the nodes T6 card ports , connected to the same network as down:

slot 1: Dual 40/100G Ethernet T62100-CR
                                e1a MAC Address:    XX:XX:XX:XX:XX:XX (auto-100g_sr4-fd-up)
                                    QSFP Vendor:         Mellanox
                                    QSFP Part Number:    332-00440
                                    QSFP Serial Number:  MTXXXXXXXXX
                                e1b MAC Address:    XX:XX:XX:XX:XX:XX (auto-unknown-fd-down)
                                    QSFP Vendor:
                                    QSFP Part Number:
                                    QSFP Serial Number: