I have an FPGA that outputs packets to a fixed IP and MAC address. That then feeds into a 40G Arista switch. The Unicast UDP packets correctly route to the destination IP and MAC. We now have another consumer who would like the same data. Can the Arista switch replicate the data and give it a new IP/Mac. How would you go about doing that?

  • 2
    It sounds like you need to use multicast instead of unicast. Unicast has a single destination IP address. This is what multicast is designed for, sending to multiple receivers which subscribe to a multicast group. Be aware that multicast doesn't use normal IP routing; you must enable multicast routing on all the routers in the path, and it will not work on the Internet, except through tunnels.
    – Ron Maupin
    Mar 24 '16 at 15:05
  • Did any answer help you? If so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you can provide and accept your own answer.
    – Ron Maupin
    Feb 19 '18 at 19:26

What model is the Arista switch? If it is a 7150 you can run it in Tap Aggregation mode (-Z license or CloudVision) and you can replicate N:1, 1:N, or N:N as tap agg mode turns the switch into a packet broker. This will not rewrite the IP/MAC though.


There are various tools around for relaying UDP packets - the idea is to send them to the relay first and then resend them to as many IP addresses/ports as you like.

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