I've spent the last few days reading as much as I could find on the old fun topic of boundary subnets vs. ranges. It get both arguments. Just reading them would lead one to believe that "best practice" on this topic is based on ones interpretation of the many articles. Such as, If the subnet is a /24, then entering it as a ‘subnet’ is best. If it is a supernet of some kind, then entering it as a ‘range’ seems to be better. So I did some testing and now I have a question about my findings. Test is based on this partial comment in one of the articles online...
----For instance, assume the network 10.100.240.0. If a machine with the address 10.100.241.15 attempts to connect, is it in the boundary? --- The answer is YES provided the subnet mask of the computer is 255.255.254.0 If the mask is 255.255.255.0, the client will have the subnet calculated as 10.200.241.0. I looked for a supernet on our network and used a /22 boundary where the DHCP gave out addresses across 4 'class C' subnets. I looked in DHCP and found a computer that was issued an address from each subnet. Then I looked each up in the SCCM console and looked at their properties. In all 4 cases the device property 'IP Subnets' showed the correct subnet entry that was created in the boundary when we used the subnet mask 255.255.252.0. Example: Create Boundary as a Subnet: 10.1.1.0, mask 255.255.252.0 results in Subnet ID=10.1.0.0 DHCP issues IP's from : 10.1.0.1 to 10.1.3.254 Find computer name for IP's: 10.1.0.100, 10.1.1.100, 10.1.2.100, and 10.1.3.100 Look up all 4 computers in SCCM and find their device property 'IP Subnets' is the same on all 4: 10.1.0.0 So... I am making the assumption that the property 'IP Subnets' in the device properties is what is used by the client to determine the boundary and is compared to the boundary Subnet ID. Am I a correct or not? If that is correct than I don't see where putting in a boundary as a supernet is a problem as the partial comment I used above would indicate. Dave
