I am having a problem with DHCP leases for clients in a school environment where the students move around quite a bit. I have setup separate subnets and scopes for each floor, however DHCP doesn't seem to know enough to remove a lease from an old scope when that client registers in a new scope, (say when they move between floors). This results in the same device getting 2 or 3 leases, when they are only using one. Combined with each person carrying a laptop/tablet and more often than not, a phone in their pocket, there are a lot of wasted addresses. Currently, I have shortened lease times to 2 minutes. but I'm looking for a solution that wont cause needless traffic with every client, their brother, and their two devices each renewing constantly.
Is there a way to get DHCP to remove a lease when it sees that client obtaining a lease from a different scope, or is there another way to approach this?