Member port of an LACP IFGRP is marked as down due to LACP key value mismatch between ports of the same IFGRP

Applies to

• ONTAP 9.2, 9.3, and 9.4
• Link Aggregation Control Protocol (LACP) interface group

Issue

• ifgrp show displays one or more ports in the multimode LACP interface group as down, which indicates that they are not participating in link aggregation
• Member port is physically up but ifgrp show displays it as down

cluster1::> ifgrp show -node cluster1-01 -ifgrp a0a

Node: cluster1-01
Interface Group Name: a0a
Network Ports: e0c, e0d
Up Ports: e0d,
Down Ports: e0c

• This issue happens randomly after node reboot or link flap
• Node shell command ifconfig -v indicates the down port has a different lag id:

cluster1::> node run -node cluster1-01 ifconfig -v

a0a: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 9000 options=6407bb<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,VLAN_HWCSU M,TSO4,TSO6,LRO,VLAN_HWTSO,RXCSUM_IPV6,TXCSUM_IPV6>

ether 02:a0:98:XX:YY:ZZ

lag id: [(8000,02-A0-98-11-22-33,0032,0000,0000),
(8000,AA-BB-CC-DD-EE-FF,0037,0000,0000)]

laggport: e0d flags=1c<ACTIVE,COLLECTING,DISTRIBUTING> state=3d<ACTIVITY,AGGREGATION,SYNC,COLLECTING,DISTRIBUTING>
[(8000,02-A0-98-11-22-33,0032,8000,0006),
(8000,AA-BB-CC-DD-EE-FF,0037,8000,00B9)]
input/output LACPDUs: 460 / 14099

laggport: e0c flags=18<COLLECTING,DISTRIBUTING> state=3d<ACTIVITY,AGGREGATION,SYNC,COLLECTING,DISTRIBUTING>
[(8000,02-A0-98-11-22-33,0033,8000,0007)
(8000,AA-BB-CC-DD-EE-FF,0037,8000,043A)]
input/output LACPDUs: 460 / 14099

• Check SystemID and Key value sent in LACPDUs of LACP Ports in ifconfig -v output
  • In the example above, storage node is sending systemID 02-A0-98-11-22-33 from each of its ports and the switch is sending systemID AA-BB-CC-DD-EE-FF
  • On same line as systemID is the Key value: 0032 sent by storage port e0d (same as lag id) and 0033 (down e0c port since it doesn't match) with 0037 from switch
• Interface group (a0a in example) is configured in non-default IPspace:

cluster1::> network port show -node cluster1-01 -port a0a -fields node,port,ipspace

cdot-vsim1-01 a0a test