[ovs-dev] Issue with OVS lacp-fallback-ab option

[Arun Navasivasakthivelsamy]

Hello folks,

We’re seeing an issue with lacp-fallback-ab option on ovs 2.5/2.6/2.8. It looks like when LACP is not enabled on the TOR switch ports, OVS on the centos server is not falling back cleanly to active-backup, and continues to send some portions of the traffic through the backup interface (we’ve seen this occur with various TOR vendor switches).  Please see the attached screenshot which shows that some traffic still hashes to backup interface. We looked at the TOR forwarding table, and MAC addresses of VMs running on this server flaps between the two corresponding TOR switch ports of the bond . I’m still in the early stages of debugging this, but wanted to reach out to you to see if this is already a known issue? If not, any help on how to debug this further will be helpful.


Thanks
-Arun