Hi ,
after reloading on vPC-Peer-Switch be box comes up and all vPC-Member-Ports on the box are in suspended state until the reload delay time expired.
Unfortunately the link of the vPC-Member Ports are already up. This behaviour leads us in some problems if we connect a Cisco-UCS-FI with a LACP-Portchannel to a vPC on N5K.
Because the link of the suspended Port is up the FI detects the port also as up and running and set it to individual state, because of missing LACP-BPDUs, So at this time the FI hast two uplinks, one Port-Channel and one individual Ports. After 30 seconds the FI starts to repinning the servers over these two uplinks. Because the individual Port is not in forwarding state an the reloaded N5K until reload delay timer expired.
So during this period all the servers which are pinned to the individual Port are blackholed.
Possible Workarrounds
1. Creating a Pin-Group for the Port-Channel and pinning all Servers to this Pin-Group to avoid in case on channel-Member goes to individual state, any server is pinned to this individual Port . This could be a solution
2.Configuring the Port-Channel on FI for "suspend individual". Unfortunately I could not find a way to achive this. This would avoid that the individual Port is considered as possible uplink-port, so no pinning to the individual Port would happen.
3. Find a way that during the delay restore time on the suspended vPC-Member-Ports also the link is down. (In my opinion this would be the best way)
I am not sure if configuration of "individual suspend" on the vPC on the N5K would help.
any other ideas?
Hubert
