Direct Server Return Loadbalancing in ACI
Direct Server Loadbalancing is a loadbalancing mechanism in which traffic is sent via a Virtual IP (VIP) to one or more Real Servers. These servers are in the same Layer 2 domain as the loadbalancer itself and will respond directly to the client without the return traffic going through the loadbalancer on the way back. This differs from loadbalancing based on source NAT or when using the loadbalancer as gateway. The following image shows Direct Server Return (DSR) Loadbalancing.