NAT Load Balancing Overview
Network Address Translation (NAT) & Load Balancing (LB) provides the ability to balance incoming traffic across multiple, similar network resources. Do not confuse this with the WAN ISP & LB feature on the SonicWall appliance. While both features can be used in conjunction, WAN ISP & LB is used to balance outgoing traffic across two ISP connections, and NAT LB is primarily used to balance incoming traffic.
Load Balancing distributes traffic among similar network resources so that no single server becomes overwhelmed, allowing for reliability and redundancy. If one server becomes unavailable, traffic is routed to available resources, providing maximum uptime.
This document details how to configure the necessary NAT, load balancing, health check, logging, and firewall rules to allow systems from the public Internet to access a Virtual IP (VIP) that maps to one or more internal systems, such as Web servers, FTP servers, or SonicWall SSL VPN appliances. This Virtual IP may be independent of the SonicWall appliance or it may be shared, assuming the SonicWall appliance itself is not using the port(s) in question.
