HA links down on the nodes with internal interconnect

• AFF A220
• AFF A150
• FAS 27XX
• HA (High Availability) Interconnect

• The HA interconnect is via the midplane and the event logs report the links as down:

Sat Oct 23 21:35:49 +0200 [node: gop_eq_thread: ic.linkStatusChange:info]: HA interconnect: Port ic0a link is down.
Sat Oct 23 21:35:49 +0200 [node: ctrl_hb_port_ic0a: ctrl.rdma.heartBeat:info]: HA interconnect: Missed heartbeat to 192.0.1.5.
Sat Oct 23 21:36:13 +0200 [node: cfdisk_config: cf.diskinventory.sendFailed:debug]: params: {'errorCode': '0', 'reason': 'HA Interconnect down'}

• The HA links may also be seen flapping in some cases.
• Cluster HA is disabled:

Cluster::> cluster ha show
 
High-Availability Configured: false
High-Availability Backend Configured (MBX): -

Warning: Cluster HA has not been configured.  Cluster HA must be configured
         on a two-node cluster to ensure data access availability in the
         event of storage failover. Use the "cluster ha modify -configured
         true" command to configure cluster HA.

• An attempt to configure HA fails with the below error:

Cluster::> cluster ha modify -configured true

Warning: High Availability (HA) configuration for cluster services requires
         that both SFO storage failover and SFO auto-giveback be enabled. These
         actions will be performed if necessary.
Do you want to continue? {y|n}: y

Error: command failed: Could not retrieve partner SFO information: entry
       doesn't exist.

• The links are reported as down on both nodes:

Cluster::*> system ha interconnect status show

                       Node: Node-01
                Link Status: down
         IC RDMA Connection: down

                       Node: Node-02
                Link Status: down
         IC RDMA Connection: down
2 entries were displayed.