Dell PowerConnect 7048P Manual page 929

2 Relay DNS packets received on VLAN 10 to 192.168.40.43
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.
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.
console(config)#ip helper-address 192.168.40.22
dhcp
6 Verify the configuration.
console#show ip helper-address
IP helper is enabled
I/F UDP Port
---- --------
Vl10 domain
Vl10 dhcp
Vl20 dhcp
Vl20 162
Any dhcp
Discard Hit Count
----- ---------
No 0
No 0
Yes 0
No 0
No 0
Configuring L2 and L3 Relay Features
Server Address
---------------
192.168.40.43
192.168.40.35
192.168.23.1
192.168.40.22
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