Question about DHCP Server and mutliple routers

kr0490

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At my work, we have the cable internet connect into an SMC modem/Router TWC controls. If I use another router as a bridge between two switches, switch 1 which the SMC router is connected directly to, and switch 2 which it is not, If i attach a DHCP server computer to switch 2, is it possible to setup the network so only devices connected to switch one use the SMC router DHCP server, and devices on the other side of our router bridge between the switches, on switch 2, use the DHCP pc server? I know this may be complecated explanation in words, so let me know if you need clarification. Thanks!
 
No a bridge is the same as connecting the switches together directly. The DHCP requests will stomp all over each other.

You would have to actually route the traffic which is not as simple as it sounds because the SMC device it not actually a router in the true sense of the word. It has no ability to send traffic for a different subnet to the router between the switches.

When you start doing things like this you need actual routers that can have multiple lan interfaces on different subnets.
 

kr0490

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If i use a D-link home router in router as opposed to gateway mode using the DD-WRT firmware, is there a way to set it up to serve this function to separate DHCP between the two subnets?
 
You best bet if you have a dd-wrt image is to define 2 lans. You would assign some of the lan port to each. You can then also define DHCP servers on the router for the lans if you like or you can just assign it to say 1 and let the other be assigned by a server. The 2 subnets will be able to communicate though the router as long as you have the gateway for the subnet set to the router. It really does not matter who give out the ip addresses to the clients as long as they know the ip to get out of the subnet.
 

kr0490

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Below is a link to a diagram of our setup. 2 cables come out of the SMC router, one to a different subnet we do not control. After the point where the cable from the main switch plugs into the d-link router, I want the other dhcp server to be in charge. It doesn't appear that my router supports port based Vlans, i asume that is what you were referring to. Is there another way to set this up?

https://app.box.com/s/b1qn5uy89ghti4aapb3kar3med0nne12

Thanks!
 
Not sure about your link then again the stupid proxy here at removes things that it thinks might have porn in it. You only option is to run the dlink router as a router and nat all the ip to that ip. It will then of course have a different subnet...3rd? that you can control with a server. Problem is with a second nat router the device on the other networks will not be able to directly access this.

When you are not actually in control of the routers that own the gateway for the subnet it make it very hard to do much network wise.