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2 DHCP pools on same L3 interface

I need to quickly and temporarily expand the number of available IPs in a DHCP pool. I can't alter the mask unfortunately; I expanded the /

24 to a /23 some months back and I don't have another /23 adjacent to it to spare. The pool is associated with a loopback. IP Unnumbered PVCs are pointed to that same loopback. What I was planning on doing was adding a secondary IP to that loopback that corresponds to my new pool. What I'm wondering is if both pools will be used as expected or if the router will only draw from the pool for the primary IP? Any ideas? I can't test this unfortunately; I'm in production.

Thanks J

Reply to
J
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It will only use the primary IP. If you are already using a /23 on the interface, don't you think it might be better to add a new subnet instead? A 512 hosts on a single broadcast domain is pretty big. If you don't really have that many hosts on the network at one time, try reducing the lease time on the DHCP server to a day or even a few hours which will free up the unused address faster.

Scott

Reply to
Thrill5

Thanks for the reply. Unfortunately I don't have a /22 to move these customers to or the time to take down 450 customers (after static reservations) and re-ip static customers. Fortunately, given this design, it isn't actually one big bcast domain. It's actually 512 of them. The ATM router does not forward bcast packets to the ATM PVCs. Each customer is entered into the routing table as a /32 dynamically. RBE is squirrelly but it works. If it wasn't for the bcast domain separation I'd agree.

There's surely an easier way to slip more IPs in there. I suppose I can peel off dynamically assigned customers and direct them to another unnumbered loopback with the expanded block. That would be slow but doable.

Thanks for the input J

Reply to
J

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