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I bought the IP address block and the machine has the Default Gateways already setup as and

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Please clarify your question (Is your machine now dual-homed, or are you moving into a new IP block and vacating your old one?) Your default gateway doesn't match your IP space, and you have two default gateways (which is possble with weighted routes or if the gateway knows about your new IP block, but IMHO unlikely). – voretaq7 Mar 17 '11 at 15:46
It is dual homed, this is a dedicated machine from a datacenter, and the IP block needs to be added on to what is already there. – Brett Powell Mar 17 '11 at 15:52
Subnet mask in use by the other IPs is – Brett Powell Mar 17 '11 at 15:56
Chicks dig guys who know how to count in binary: – Evan Anderson Mar 17 '11 at 18:23
up vote 3 down vote accepted -

subnet: broadcast:

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... and what if there's a router in there? or a HSRP pair? You've noted the two addresses Brett definitely can't use but we don't have enough information yet to know if his ISP's infrastructure is burning more than just those two... – voretaq7 Mar 17 '11 at 15:47
I'm working on the assumption that the thrust of the question was "what range does this cover". If all but one of his range are in use already then he has one left, but it would seem logical that the ISP would have told him how many addresses he'd lose. – Sirex Mar 17 '11 at 15:55
ISPs around here can be pretty awful about telling you stuff like that until you ask (or step on one of their routers' HSRP addresses). That said assuming his current router(s) are smart enough to handle the new addresses he could theoretically use the whole range excluding the network/broadcast IPs. – voretaq7 Mar 17 '11 at 15:58
I added a comment to the initial post with more info, does that help? – Brett Powell Mar 17 '11 at 15:59

pretty useful

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