Users Guide

Table Of Contents
Layer-2 and Layer-3 Relay Features 1251
console(config-if-vlan10)#ip helper-address 192.168.40.35
domain
console(config-if-vlan10)#exit
3
Relay SNMP traps (port 162) received on VLAN 20 to 192.168.23.1
console(config)#interface vlan 20
console(config-if-vlan20)#ip helper-address 192.168.23.1 162
4
The clients on VLAN 20 have statically-configured network information,
so the switch is configured to drop DHCP packets received on VLAN 20
console(config-if-vlan20)#ip helper-address discard dhcp
console(config-if-vlan20)#exit
5
DHCP packets received from clients in any VLAN other than VLAN 10
and VLAN 20 are relayed to 192.168.40.22.
console(config)#ip helper-address 192.168.40.22 dhcp
6
Verify the configuration.
console#show ip helper-address
IP helper is enabled
NOTE: The following command is issued in Global Configuration mode, so it
applies to all interfaces except VLAN 10 and VLAN 20. IP helper commands
issued in Interface Configuration mode override the commands issued in
Global Configuration Mode.
I/F UDP Port Discard Hit Count Server Address
---- -------- ----- --------- ---------------
Vl10 domain No 0 192.168.40.43
Vl10 dhcp No 0 192.168.40.35
Vl20 dhcp Yes 0
Vl20 162 No 0 192.168.23.1
Any dhcp No 0 192.168.40.22