IP Helper/DHCP Relay Commands 955Command ModeInterface (VLAN) Configuration modeUser GuidelinesEnable DHCP Relay using the ip helper enable command. The interfaceconfiguration always takes precedence over global configuration. However, ifthere is no interface configuration, then global configuration is followed.ExampleThe following example enables the circuit ID and remote agent ID options onvlan 10.console(config)#interface vlan 10console(config-if-vlan10)#ip dhcp relay information option-insertip helper-address (global configuration)Use the ip helper-address (global configuration) command to configure therelay of certain UDP broadcast packets received on any interface. To delete anIP helper entry, use the no form of this command.Syntaxip helper-addressserver-address [dest-udp-port | dhcp | domain | isakmp |mobile-ip | nameserver | netbios-dgm | netbios-ns | ntp | pim-auto-rp | rip| tacacs | tftp | time ]no ip helper-address [server-address] [dest-udp-port | dhcp | domain |isakmp | mobile-ip | nameserver | netbios-dgm | netbios-ns | ntp | pim-auto-rp | rip | tacacs | tftp | time ]•server-address — The IPv4 unicast or directed broadcast address to whichrelayed UDP broadcast packets are sent. The server address cannot be anIP address configured on any interface of the local router.•dest-udp-port — A destination UDP port number from 0 to 65535.•port-name — The destination UDP port may be optionally specified by itsname. Whether a port is specified by its number or its name has no effecton behavior. The names recognized are as follows: dhcp (port 67), domain
