All Barracuda Link Balancers, Firmware Version 1.0.029 and above
In order for the Barracuda Link Balancer to pass VPN traffic without issue, first ensure that the proper inbound firewall rules have been configured to allow traffic into your network as explained in Solution 00003689. Then configure inbound port forwarding rules as described in Solution 00003692. Choose the Listen Interface the VPN connection will travel across and configure port forwards for UDP on ports 500 and 4500. Once complete, configure a forward for the ESP protocol.
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