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I have recently had a 2mb EFM connection installed in a charity I work for. We were not supplied a router because we already had a watchguard XTM330 in storage ready to be used. The line is presented by a Hatteras HN408-CP which I've plugged into the first port of the Watchguard using a crossover cable. This is configured as an external interface.

My first problem is that I was provided with an ip address that is on a different subnet to the ip of the gateway they have supplied. On the Watchguard I have configured an external interface with static IP, which I assume is correct for EFM. When i enter the IP and the Gateway the Watchguard gives an error: "The netowrk (sic) address and the Gateway are on different Networks."

The second problem is that the EFM provider has said that all outgoing traffic should be tagged with a vlan id, but there is no option to do this when configuring an external interface on the Watchguard. How do I go about doing this?

Any help would be greatly appreciated.

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  1. Telling us that "I was provided with an ip address that is on a different subnet to the ip of the gateway they have supplied." without giving us more detail doesn't give us enough information to help.

  2. You could plug the external interface of the Watchguard into a VLAN capable switch, plug the HN408-CP into the same switch, configure the VLAN on the switch and configure the ports accordingly. I'm pretty sure you're going to have to configure the switch port that the HN408-CP is connected to as a trunk port so that the VLAN tag remains intact as it enters that switch port.

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For 2, is there no way to set this up on the watchguard itself? I can create a VLAN interface on one of the spare Watchguard ports – Mark Jan 15 '13 at 13:10

I worked it out - was a matter of creating a vlan interface on one of the ports, going to VLAN configuration, tagging all traffic and creating an external interface from within the vlan interface, not as a regular external interface

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I have a very similar situation with my Leased Line I have a Watchguard XTM 510 My WAN subnet and Routed IP subnet are different. Please could you send me a version of you config so I can try setting my Watchguard in the same way – user187358 Aug 27 '13 at 14:51

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