Deployment KB: VxRack ToR Nexus 9332PQ switches with 40Gb to 10Gb cannot be port-channeled


   Article Number:     529886                                   Article Version: 4     Article Type:    Break Fix 




VxRack AS





User requested that the VxRack system be connected to their network via a 40Gb port channel broken out into 4 10Gb subinterfaces from the Nexus 9332PQ uplinks to a pair of Catalyst 6800 switches. (See diagram for detail).   

      User-added image   
    When performing the network uplink task, the port channel would not come up.   
    Received a "port not compatible [Buffer boost]" error message.                                                           






There is a Cisco bug for this scenario, CSCux08987, but no resolution at this time. Refer to Cisco bug for complete information:                                                           






The user contacted their Cisco SE. A workaround was found to configure "no buffer-boost" on all of the sub-interfaces in the Nexus 9332PQ switch. This enables the port channel to come up.