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DaveC_53879's avatar
DaveC_53879
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Jul 12, 2017

NATing forwarded addresses

We have a pool of RADIUS servers being load-balanced by an F5. The servers need to see the address of the requester so we don't have source NAT enabled, and the servers are not on the same network as the F5 nor the requesters, so what we do is force traffic from the RADIUS servers back through the F5 using policy based routing, and then have forwarding VIPs for each server. In the forwarding VIPs, the IP of the RADIUS server is the source and 0.0.0.0/0 is the destination. This is all UDP traffic. I see that the source address of routed/forwarded traffic from the F5 to the original requester is being NATed to the original VIP address, but I don't know how it's being NATed. That's what I need to figure out. There is no SNAT on the original VIP nor on the forwarding VIPs.

 

  • Is there a way to see the process that's doing the NATing? I've been looking for this for 2 days. Thanks in advance.

     

  • If you are trying to see if the F5 is NAT/SNAT the IP address, you can try the following commands:

    show ltm nat
    show ltm snat
    show sys connection {options} {IP-Address}