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Split downstream on uBR7223

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Split downstream on uBR7223

Hello all!
I've got what I suspect to be a simple issue here... I'm an IP network guy by trade, so forgive me if this is a ridiculous question :)

I have a CMTS with a downstream that's loaded. I have a second linecard that I'd like to activate, and have split the HFC plant (or a node, specifically) to accomodate this: I now have physically separate up and downstream paths for the node so that I can run my second linecard on that node, and run our busiest node on that card.
We run the ISC DHCP server on linux boxes behind the uBR using the cable helper-address config directive.

My question is this:
How do I go about splitting the IP traffic between the cards? Is the uBR 'smart' enough to know that a DHCP request is from Cable 2/0 vs. c3/0? Do I need to run separate subnets on the 2 cards for the modems and CPE's? Or will the uBR figure out where the traffic is coming to/ from? Is there a way to bridge the 2 linecards on an IP level, without having collisions on the RF level or other badness?

Thanks very much in advance for your input!


Regular node split?

It sounds like you're describing a standard node split. You'll have to create new subnets for the second card, or put both cards into a cable bundle (bridge group). I don't operate Cisco CMTSs so I can't really provide a configuration for doing that.

If you get stuck trying to do a cable bundle, just add new subnets on the second blade instead. That should be pretty simple to set up.

It sounds that way to me

It sounds that way to me too... I'll implement a cable bundle and call it done:


Thanks very much for your reply!

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