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John_131301's avatar
John_131301
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Jan 23, 2015

Port Fail-over

I have two 10G connections going from my LTM to two different cisco switches. Each port on the cisco switch is configured for vlan tagging 802.1Q. How can I configure the LTM to provide port fail over in the event one of the 10G interfaces goes down? I currently have one of the 10G interfaces configured and added to a vlan as a tagged interface.In the very near future we will be adding additional vlans and want all vlans to use the 10G interface.

 

8 Replies

  • I would suggest Cross-Stack Etherchannel(or distributed LACP) and create one big LACP trunk on the BigIP device. All your VLANs can be added to that trunk and you can utilize all links and have redundancy.

     

    • John_131301's avatar
      John_131301
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      If I create a trunk on the BigIP that creates an ether channel, won't this cause spanning tree to disable one of the ports on the cisco switch?
    • Brad_Parker_139's avatar
      Brad_Parker_139
      Icon for Nacreous rankNacreous
      Not if your switches support Cross-Stack Etherchannel also known as distributed trunking(HP calls it LACP-dt). With distributed trunking, Spanning Tree is not needed.
  • I would suggest Cross-Stack Etherchannel(or distributed LACP) and create one big LACP trunk on the BigIP device. All your VLANs can be added to that trunk and you can utilize all links and have redundancy.

     

    • John_131301's avatar
      John_131301
      Icon for Nimbostratus rankNimbostratus
      If I create a trunk on the BigIP that creates an ether channel, won't this cause spanning tree to disable one of the ports on the cisco switch?
    • Brad_Parker's avatar
      Brad_Parker
      Icon for Cirrus rankCirrus
      Not if your switches support Cross-Stack Etherchannel also known as distributed trunking(HP calls it LACP-dt). With distributed trunking, Spanning Tree is not needed.
  • THi's avatar
    THi
    Icon for Nimbostratus rankNimbostratus

    Isn't Cross-Stack Etherchannel link aggregation within a Cisco switch stack instead of two separate Cisco switches? I guess you were referring to "dual homing" BIG-IP to two separate switches.

     

    I have a customer whom we helped to use two separate Nexus switches, with Virtual PortChannel (vPC), to dual home a BIG-IP pair with crossed LACP links and that works fine in this scenario. I assume Cisco VSS can do about the same. As Brad mentions spanning tree is not needed - and not recommended either..