Configuring DHCP Server Settings 853What Additional DHCP Features Does the Switch Support?The switch software includes a DHCP client that can request networkinformation from a DHCP server on the network during the initial systemconfiguration process. For information about enabling the DHCP client, see"Setting the IP Address and Other Basic Network Information" on page 105.If the switch is functioning as a Layer 3 device, the Layer 3 DHCP RelayAgent can relay DHCP messages between DHCP clients and DHCP serversthat are located in different IP subnets.The DHCP Layer 2 Relay feature permits Layer 3 Relay agent functionality inLayer 2 switched networks. The switch supports L2 DHCP relayconfiguration on individual ports, link aggregation groups (LAGs) andVLANs. For information about Layer 2 and Layer 3 DHCP Relay, see"Configuring L2 and L3 Relay Features" on page 899.DHCP Snooping is a security feature that monitors DHCP messages betweena DHCP client and DHCP server. It filters harmful DHCP messages andbuilds a bindings database of (MAC address, IP address, VLAN ID, port)tuples that are specified as authorized. DHCP snooping can be enabledglobally and on specific VLANs. For information about DHCP Snooping, see"Snooping and Inspecting Traffic" on page 751.Default DHCP Server ValuesBy default, the DHCP server is disabled, and no address pools are configured.You must create at least one address pool and enable the DHCP server toallow the switch to dynamically assign network information to hosts withDHCP clients that broadcast requests.The DHCP server can lease a maximum of 256 addresses.
