I have a network with a DHCP server and RADIUS authentication.
Clients connect to my network, get a DHCP address, enter the signing in page, input their prepaid cards, and get to the Internet.
We sometimes see some clients (was once malicious) connect a router to one of my Access Points and they don't disable DHCP functionality on that router… The entire network falls apart, until we disconnect that actor or re-configure his router correctly to disable DHCP, and allow that router to take a DHCP lease from the main DHCP server we control.
So How do I force my network to only honor the DHCP server I control?
In fact, the whole problem I see now is a packet loop. I'm assuming it's someone who's connected a wrongly configured router with DHCP enabled. So I'm trying to disallow anyone from assuming DHCP role.
DHCP Server is at 192.168.1.5 (RouterBoard device)