Default DHCP Snooping Configuration Table 1: Default DHCP Configuration 1 The switch responds to DHCP requests only if it is configured as a DHCP server. 2 The switch relays DHCP packets only if the IP address of the DHCP server is configured on the SVI of the DHCP client. 3 Use this feature when the switch is an aggregation switch that receives packets with option-82 information from an edge switch. DHCP Snooping Configuration Guidelines • If a switch port is connected to a DHCP server, configure a port as trusted by entering the ip dhcp snooping trust interface configuration command.
Configuring DHCP Default DHCP Snooping Configuration Feature Default Setting DHCP server Enabled in Cisco IOS software, requires configuration1 DHCP relay agent Enabled2 DHCP packet forwarding address None configured Checking the relay agent information Enabled (invalid messages are dropped) DHCP relay agent forwarding policy Replace the existing relay agent information DHCP snooping enabled globally Disabled DHCP snooping information option Enabled DHCP snooping option to accept packets on untrusted input interfaces3 Disabled DHCP snooping limit rate None configured DHCP snooping trust Untrusted DHCP snooping VLAN Disabled DHCP snooping MAC address verification Enabled Cisco IOS DHCP server binding database Enabled in Cisco IOS software, requires configuration.
Note The switch gets network addresses and configuration parameters only from a device configured as a DHCP server. DHCP snooping binding database agent Enabled in Cisco IOS software, requires configuration. This feature is operational only when a destination is configured. Configuring DHCP 9