Symptom
Output is not load balanced between members of a san-port-channel.
Conditions
Nexus 6000 or Nexus 5600
san-port-channel either in TNP mode or TE
Traffic with varying OXID and the vsan loadbalancing is src-id/dst-id/oxid.
The traffic going out of the san-port-channel switch is sent on only one of the members of the san-port-channel.
Workaround
Even for native fibre channel, internally it is handled as FCoE.
Change the load balancing to
port-channel load-balance ethernet source-dest-port
There is no impact the ethernet or IP.
Further Problem Description
For example, fc3/15 and fc3/16 are members of the same san-port-channel.
N56001# show int fc3/15-16 | i "output rate"
1 minute output rate 1479490336 bits/sec, 184936292 bytes/sec, 89332 frames/sec
1 minute output rate 458704 bits/sec, 57338 bytes/sec, 72 frames/sec
Resolution Summary
Print the following syslog when creating the first san-port-channel, vfc-port-channel or vfc that is bound to port-channel and when the algorithm is different than source-dest-port.
FC/FCoE load balancing is based on the source ID, destination ID and exchange ID (OX ID).
To achieve this, it is recommended to configure "port-channel load-balance ethernet source-dest-port.
