BMC not passing network traffic, while the e0M is passing traffic normally

Applies to

• AFF-A800
• ONTAP 9
• BMC

Issue

• The BMC of an AFF-A800 will not pass traffic via e0M (connecting to SP/BMC)
• While ONTAP passes traffic over e0M (connecting to node mgmt Lif) without any issue
• ONTAP reports the BMC as online

::> net port show
  (network port show)
 
Node: clusterA-01
                                                  Speed(Mbps) Health
Port      IPspace      Broadcast Domain Link MTU  Admin/Oper  Status
--------- ------------ ---------------- ---- ---- ----------- --------
e0M       Default      bd_mgmt          up   1500  auto/1000  healthy  

• However Sysconfig -a reports ethernet link as 'Down'.

	Service Processor           Status: Online
		Firmware Version:   10.4
		Mgmt MAC Address:   00:a0:98:f1:19:2e
		Ethernet Link:      down
		Using DHCP:         no
	IPv4 configuration:
		IP Address:         10.9.51.230
		Netmask:            255.255.255.0
		Gateway:            10.9.51.1
	IPv6 configuration:         Disabled

• May also notice the following system Health Alert

::> system health alert show
               Node: clusterA-01
           Resource: SP Config
           Severity: Major
    Indication Time: Thu Jun 25 14:12:35 2020
           Suppress: false
        Acknowledge: false
     Probable Cause: Service Processor in node clusterA-01 has no
                     network connectivity. The cable between the Wrench port
                     on the controller and the ethernet switch is
                     disconnected.
    Possible Effect: You might not be able to use the Service Processor to
                     remotely access, monitor, and troubleshoot your
                     storage system.
Corrective Actions: 1. Check the connection between the Wrench port and the ethernet switch.
                     2. If the cable is properly connected, ensure that the Service Processor's ethernet interface is configured properly by executing the command "system service-processor network show".
                     3. Check for network cable related issues.
                     4. Contact the technical support if the alert persists.