The controllers contain an internal DHCP server. This server is typically used in branch offices that do not already have a DHCP server.
The wireless network generally contains a maximum of 10 APs or less, with the APs on the same IP subnet as the controller.
The internal server provides DHCP addresses to wireless clients, direct-connect APs, and DHCP requests that are relayed from APs. Only lightweight access points
are supported. When you want to use the internal DHCP server, ensure that you configure SVI for client VLAN and set the IP
address as DHCP server IP address.
DHCP option 43 is not supported on the internal server. Therefore, the access point must use an alternative method to locate
the management interface IP address of the controller, such as local subnet broadcast, Domain Name System (DNS), or priming.
Also, an internal DHCP server can serve only wireless clients, not wired clients.
When clients use the internal DHCP server of the controller, IP addresses are not preserved across reboots. As a result, multiple clients can be assigned to the same IP address. To
resolve any IP address conflicts, clients must release their existing IP address and request a new one.
Wired guest clients are always on a Layer 2 network connected to a local or foreign controller.