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Question from Jangsters
“While I was still setting up my test lab(migrating windows 2000 upgrade), I came upon this question. We currently have about 175 employees and we are planning to expand maybe 100 more people. My question is, since we have only one domain and one subnet, wont we run out of IP addresses since the DHCP server will hand out only 254?
My thought was that I would have to create a different subnet and segment the network. While I was researching this, segmenting the network seems to just do that. Even if I have only 254 addresses, I can segment the network w/ 2 different subnets with each segment having only 127 IP addresses.
What is the proper way to resolve this situation. Im thinking if I add to need subnets and do some segmenting, I should do it now in the process of upgrading(windows 2000 server) to be ready for the future. Your help would be greatly appreciated. Thank You.”
Answer from 87C751
“Right you are. You need another subnet (or two, for expansion room).
Another possibility is to set up a router that will do NAT, and partition yourself a few subnets in 192.168.x.x. With a netmask of 255.255.0.0, theyll all still be able to talk to each other and the whole lab uses one public IP. If you need to run outside-accessable servers in the lab, do port forwarding on the router (though if your original setup is DHCP, Id guess youre not running any outside-accessable servers). This does make Windows Networking between the lab and outside difficult, however. “
Answer from MrSneaky
“Ya the easiest solution is change the subnet to allow more IPs on the subnet. For example if you were using 192.168.0.x-255.255.255.0.
you can use the subnet 255.255.254.0 which will allow you to use 192.168.0.x and 192.168.1.x. If you are commited to keeping one unsegmented network maybe something like the other post suggest – 192.168.x.x using 255.255.0.0. Of course you can change to a class A address of 10.x.x.x 255.0.0.0.”
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