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I've got two separate WAN connections with DHCP on both of them; can I connect these to two different VLANs using Cisco gear (so VLAN 0 gets one WAN and VLAN 1 gets the other?)

Apologies I'm inexperienced with Cisco gear, but am in the position of having to purchase and deploy it.

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So - to clarify: how do you have DHCP on a WAN connection? Generally I would think you were asking: "I have 2 WAN connections, terminating in 2 routers, which each serve DHCP. I want to use one piece of Cisco gear to receive both WANs, and then use VLANs to serve 2 different DHCP scopes to two different subnets, which will each use a separate WAN gateway." Is that correct? – Driftpeasant Dec 1 '11 at 15:55
Yes, that's exactly correct. – chrism2671 Dec 1 '11 at 17:00
Then yes, it is technically possible. I have a similar setup at one of my clients. I have no earthly idea what code the network admin did to use it, though. :) – Driftpeasant Dec 1 '11 at 20:44

Cisco routers allow you to do "source based" routing using ACLs. This would allow you to route multiple subnets/vlans to separate WAN connections. Most Cisco routers could also support both WANs attached directly to them with no need for additional equipment in front of them (except for your modem/iad/etc).

You may find this helpful:

Your question is a little ambiguous, so I'll just add -- you would still be able to do this if these "WAN" connections where two separate private subnets behind their own routers.

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