OK, so I have a subnet (192.168.11.0) that currently has all servers and clients on it. It's running out of addresses. So, I create a new subnet (192.168.12.0) and change my DHCP server (Fortigate ...

Today, the standard methods for moving the network/host address boundary are variable-length subnet masking (VLSM) for host addressing and routing inside a routing domain, and classless interdomain ...

Is there an easy way (like via a .Net library) that allows me to get the IP address and subnet mask of the local machine that the application is running on?

If a device is not able to get an IP address when on a network, and results in DHCP Lookup Failed, then this post will help you fix it.