We have multiple locations and we are migrating our internal IP network from 172 dot to 10 dot address scheme. I've added a secondary address on each of our routes for the 10 dot scheme and everything seems to work. DHCP servers are located at our central office and IP Helper is set and working on all Routers. I've created the 10 dot scopes and leases on the 172 dot scopes are currently set to a short lease (1 hour). I've changed static devices at our remote location to the 10 dot network scheme and they work correctly.
At the end of business (Friday) I instructed the remote location to shutdown all PC's and I inactivated their current scope and activated their new scope. When the users attempted to boot on Monday they could not get an address. I tried ipconfig /flusdns and /registerdns and still no luck. I had to reactivate their old scope. I've been told that I may have to change the primary address on the remote router from 172 dot to 10 dot to allow the new DHCP scope to work. I like some feedback on whether this is the problem.