Route Mode
About
In a Route Mode Topology, the TR7 Load Balancer only performs routing, and SNAT is not used. This ensures that the Client IP address is preserved and visible in the Backend Service logs. This approach provides lower latency, especially for large-scale enterprises and organizations.
In a Route Mode Topology, packets from the client are forwarded to the Backend Service through TR7. However, return packets bypass TR7 and are sent directly to the client, resulting in packet drops. This is referred to as Asymmetric Routing. Asymmetric traffic flow can lead to packet loss due to firewalls, routing rules, or reverse path filtering mechanisms. To resolve this issue, Policy Based Routing should be implemented to enforce the return of client packets through the Load Balancer.
Example Topology
In an example Route Mode Topology, TR7 is shown utilizing two network interfaces: VLAN 20 and VLAN 30. The 192.168.20.77 IP address on VLAN 20 is designated as the vService IP address. Similarly, the 192.168.30.77 IP address is assigned as the VIP for VLAN 30.
Policy Based Routing is applied on the firewall to route requests from the VLAN 30 network to the 192.168.30.77 IP address on TR7. This enables the client to send requests to VLAN 20, ensuring that traffic is successfully delivered without using Source NAT (SNAT) on either the firewall or TR7. This also preserves the Client IP address.
Interface
Step > 1
Navigate to "Network > Route Tables" and create two separate route tables for VLAN 20 and VLAN 30.
Step > 2
Under "Network > Interfaces", assign the relevant network interfaces to the created Route Tables, configure their IP addresses, and define default gateways.
Step > 3
In "Traffic Manager > Backend Services", select the Route Table as VLAN 30 for the relevant server. Enable Details and set "Use Client IP" under the SNAT section.
Step > 4
Finally, create a vService using the 192.168.20.77 VIP address under the vServices menu and assign the relevant Backend Service as the default.