BT Business Infinity - Static IP failure / mystery

[BigRich100]

I should start by saying that BT Helpline has tried to help with this but as I've discovered fixed IP in BT world doesn't seem to be the same as it is with any other provider I've ever come across. So much so that they can't offer any box / service that can just provide straight forward NAT translation from the public addresses to private ones. To be frank unless this can be resolved I feel I may have to cancel the BT service and start again with a different provider.

I was advised by BT that to solve by problems I would need a router / firewall that supported PPPoE and so I ordered a Sophos UTM firewall. It was reasonably straightforward to setup and works well in just basic connection.

What seems to be impossible is to get three of my five external static IP's to three internal static IP's (192.168.1.x) using any of the setup's suggested (masquerade IPs etc.)

PLEASE can anyone let me know if you have any experience on getting this working as to be frank I seem to be chasing the impossible here.

[andyt22]

I've no experience of the Sophos UTM firewall but I do know that not all firewall/routers support mapping multiple external static IP addesses to explicit internal static IP addresses - most will only map from a single external static address to a block of internal addresses using NAT.

Your requirements sound similar to mine and the solution I adopted was to route all the external static IP addresses straight through the BT Hub3 onto the internal LAN with the hub's firewall feature disabled and then to use a firewall/router on the LAN to do the external/internal address mapping. The firewall/router needs a minimum of two Ethernet interfaces and doesn't need to support PPPoE (as this is handled by the BT Hub3). For maximum flexibility, a BSD-based firewall/router is best as they are very configurable and will certainly support what you are trying to do. They certainly work for me.

Andy