Services on the Barracuda Load Balancer can be deployed in the following three modes:
All of these deployment modes require specific network configurations. The Barracuda Load Balancer must be in either Route-Path or Bridge-Path mode. Direct Server Return is an option that you may choose for each Real Server.
Choose the deployment mode for the Barracuda Load Balancer based on the type of network configuration that currently exists at your site as well as on the types of Services you wish to load balance. Route-Path is recommended over Bridge-Path because it provides a more robust deployment. Enabling the Direct Server Return option is recommended only for Real Servers that generate a much greater volume of outbound traffic relative to the inbound traffic.
A Service is the access point that the client uses for the functionality provided by the Real Servers. There are multiple Service types supported by the Barracuda Load Balancer. Because the choice of Service type may affect the deployment method, this table gives a brief overview.
Table 1. Service Types.
Layer 4 - TCP
|Traffic passes in half-NAT mode, meaning the destination IP address is changed to that of the Real Server, but the source IP address remains intact.|
|Traffic passes in full-NAT mode, meaning that both the source and destination IP addresses are changed. The Barracuda Load Balancer acts as a full proxy. Connections from the client are terminated at the Barracuda Load Balancer and new ones are established between the Barracuda Load Balancer and the Real Servers.|
Secure TCP Proxy
|Same description as their non-secure counterparts. In addition, Services with this type perform SSL offloading using a certificate that is specified when the Service type is selected.|