Forum Discussion

sandy16's avatar
sandy16
Icon for Altostratus rankAltostratus
Dec 14, 2012

F5 and Cisco Nexus VPC

Hi, my network design is as follows: I have a pair of F5-ltms connected to a pair of nexus 5k. In other words, each ltm is dual connected to both the cisco n5ks in a vpc-fashion. My N5ks are purely layer-2, and all the layer-3 is handled on a one hop up by on a different set of switches. Are there any special recommendations to this design? As F5 uses "auto last hop" feature by default, so I believe it will always reply back to individual mac-address of the n5k instead of the vpc-system-mac. Is this correct? Has anyone seen any issues in this..?

 

config
design

1 Reply

Sort By
  • Josh_Abaire's avatar
    Josh_Abaire
    Icon for Nimbostratus rankNimbostratus
    Dec 14, 2012
    Why would the F5 ever reply to the 5k? If the 5k is strictly layer 2, it would be replying to the MAC of the layer 3 address. The only issue is when the 5k has a VPC to the layer 3 device such as a 7k and it is running HSRP. You'll want to have peer-gateway enabled since you cannot control if that traffic destined to that MAC will hit the A side or the B side and the 7k will not forward that traffic across the vPC peer-link.