The Barracuda Link Balancer can act as a firewall, inspecting arriving network traffic and allowing or denying passage based on inbound, outbound, 1:1 NAT, and port forwarding rules. Some of these functions are available even if the firewall function is disabled.
Using 1:1 NAT and port forwarding rules, the Barracuda Link Balancer can perform:
- 1:1 NAT - Assign external addresses to internal clients.
- Port forwarding (or Port Address Translation) - The traffic to a port across one or multiple links is directed to an internal client.
- Many to 1 NAT - One internal server may receive traffic from more than one WAN link. You can achieve this by creating 1:1 NAT rules or port forwarding rules.
- Port blocking and unblocking.
Inbound and outbound firewall rules are executed regardless of firewall status. Port forwarding and 1:1 NAT rules are executed only if the Barracuda Link Balancer firewall is enabled or, for any WAN link with the NAT/Port Forwarding option enabled (even if the Barracuda Link Balancer firewall is disabled). Rules can always be created and saved even when they cannot be executed. This allows you to configure the built-in firewall with minimal disruption to your network.