Soon I'll be in the posistion of having access to 3 Wan circuits (2 ADSL and 1 Cable modem). I've a 2820 which can easily cope with 2, but I was thinking of adding in a spare 2910 I have to allow all three to be used.

My thinking is to have the setup connected as follows:

2910 WAN 1 - Cable
2910 WAN 2 - ADSL Provider 1 via ADSL Modem (Possible a Vigor 100 or the orginal ISP DLink in Bridge mode)

2820 WAN 1 - ADSL Provider 2
2820 WAN 2 - Connected to the a LAN port of the 2910.

The 2820 would have the main LAN that users would hang off of, the LAN of the 2910 would just be used to route between the two devices.

I'd like all the VPNs to terminate on the 2820, but be available from any WAN connection.

I've a block of real world IP space (from ADSL 2) I can make available for use on the 2910/2820 interconnection. I'm wondering if this will be the best way for too allow all the VPN terminations to work correctly, as it will allow me to switch off NAT on the 2910.

I'm guessing I'll need to be clever with the load balancing rules across both devices if this is to work well, but it could just be that load balancing is implemented to be effectivly across Cable and ADSL 2 connections, with ADSL 1 just acting as a failover connection should I lose the Cable connection.

I know it isn't your normal setup, but any thoughts on how this may best be configured in practice - I'm all ears. I'll be starting to put this together towards the end of the week.

The 3300V+ can take up to 4 WAN connections and 4 LAN Subnets, and is only £317+VAT at broadbandbuyer.co.uk

We have bought one instead of doing what you suggest. We did do it your way, but at that price it was way easier than doing what you suggest. Especially as you do not have to be creative with the load balancing.

Due to throughput limitations on the 2910 I had to rethink my plans - my Cable connection is 50Mb but the 2910 maxs out at around 20. Thought I'd post the current setup in case it helps anyone else down the line.

2820 WAN1 - ADSL from Zen
2820 WAN2 - Cable from Virgin via Virgin's "SuperHub"

2910 WAN1 - ADSL from TalkTalk via TalkTalk Dlink in Bridge Mode

The LANs of the 2820 and 2910 are in the same subnet. This has allowed me to add two default GW's with weighted metrics to my clients giving me resliance of kit and ISP connectivity - which is an improvement over my original plan.

Currently the virgin connection is set as the preffered route in the load balancing rules. Clients who require TalkTalk for their SMTP, have static routes added on the client for the SMTP servers.

Testing has shown failover works well on ISP outage and is also pretty swift on a router outage too.

Still to do:

I need to complete the VPN config on the 2910, but this will duplicate the config of the 2820 for resilance purposes (at least for dial in connections to allow me to manage the network remotely).

I'm thinking of adding the Virgin connection into the 2910's WAN2 port as well. This will allow this fast connection to still be used should the 2820 go bang (albeit at the throttled throughput of the 2910).

Due to the Virgin connection being Natted to the 2820, I need to run a client internally to get the dyndns updated, as the one on the Draytek won't publish the correct IP.

Getting there though!