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After reading about FreeBSD aggregation we think we are set but it's still not clear to me.

Switch is a Cisco 2960S (software 15.x), Client is a Mac Pro running Mavericks. I don't know if the BSD internals are the same, but don't expect they have changed much over the years. Mac Pro is a medical clinic client's server (required for their application).

Below is what I’m seeing on my switch and according to the article, one sets the switch ports to active, then the flags show the peer as SA, meaning the peer is Active thus the contradiction. If the switch is set to active, I would expect the peer to be passive.

Switch#sh lacp neighbor 
Flags:  S - Device is requesting Slow LACPDUs 
        F - Device is requesting Fast LACPDUs
        A - Device is in Active mode       P - Device is in     Passive mode     

Channel group 1 neighbors

Partner's information:

                  LACP port                        Admin  Oper      Port    Port
Port      Flags   Priority  Dev ID          Age    key    Key       Number  State
Gi0/47    SA      32768     003e.e1cb.71d4  24s    0x0    0x1    0x4     0x3D  
Gi0/48    SA      32768     003e.e1cb.71d4  24s    0x0    0x1    0x5     0x3D  
Switch#sh lacp nei de
Flags:  S - Device is requesting Slow LACPDUs 
        F - Device is requesting Fast LACPDUs
        A - Device is in Active mode       P - Device is in    Passive mode     

Channel group 1 neighbors

Partner's information:


          Partner               Partner                     Partner
Port      System ID             Port Number     Age         Flags
Gi0/47    32768,003e.e1cb.71d4  0x4              25s        SA

          LACP Partner         Partner         Partner
          Port Priority        Oper Key        Port State
          32768                0x1             0x3D

          Port State Flags Decode:
          Activity:   Timeout:   Aggregation:      Synchronization:
          Active      Long       Yes            Yes

          Collecting:   Distributing:   Defaulted:   Expired:
          Yes           Yes             No           No 

          Partner               Partner                     Partner
Port      System ID             Port Number     Age         Flags
Gi0/48    32768,003e.e1cb.71d4  0x5              25s        SA

          LACP Partner         Partner         Partner
          Port Priority        Oper Key        Port State
          32768                0x1             0x3D

          Port State Flags Decode:
          Activity:   Timeout:   Aggregation:      Synchronization:
          Active      Long       Yes            Yes

          Collecting:   Distributing:   Defaulted:   Expired:
          Yes           Yes             No           No 
Switch#

Thank you

2

I think you're misunderstanding the active/passive concept in LACP link aggregation.

What is active or passive are the ports partecipating in the aggregation.

So in your case, both the switch and the PC have agreed on an active/active configuration, i.e. both ports are actively carrying traffic, load balancing between them.

If you prefer, you can force one of the ports to become passive, i.e. won't actively transport taffic unless the current active port goes down.

Because you're using LACP, it should be sufficient to configure, for example,

interface  Gi0/48
 channel-group 1 mode passive

and then the PC will negotiate correctly on its side.

  • Thank you for your quick reply. That clears it up. I was thinking they had to be setup complimentary, meaning opposite. So active/active means we are actively load balancing across interfaces, but if I set one side to active/passive, passive being the switch, that interface is idle until active fails. – Dacid Salin Oct 4 '18 at 16:51

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