nPath Routing - Direct Server Return (BIG-IP v11.4 - v13: LTM)

This document provides guidance for configuring the BIG-IP system version 11.4 and later for nPath routing (also known as Asymmetric routing or Direct Server Return (DSR)).

With the nPath routing configuration, you can route outgoing server traffic around the BIG-IP system directly to an outbound router. This method of traffic management increases outbound throughput because packets do not need to be transmitted to the BIG-IP system for translation and forwarding to the next hop.

In bypassing the BIG-IP system on the return path, nPath routing departs significantly from a typical load-balancing configuration. In a typical load balancing configuration, the destination address of the incoming packet is translated from that of the virtual server to that of the server being load balanced to, which then becomes the source address of the returning packet. A default route set to the BIG-IP system then sees to it that packets returning to the originating client return through the BIG-IP system, which translates the source address back to that of the virtual server.

Published June 12, 2018