Dell PowerConnect 6224 Command Line Interface Manual page 713

Default Configuration
No helper addresses are configured.
Command Mode
Interface Configuration (VLAN) mode.
User Guidelines
This command can be invoked multiple times on routing interface, either to
specify multiple server addresses for a given port number or to specify
multiple port numbers handled by a specific server.
The command no ip helper-address with no arguments clears all helper
addresses on the interface.
Example
To relay DHCP packets received on vlan 5 to two DHCP
servers, 192.168.10.1 and 192.168.20.1, use the
following commands:
console#config
console(config)#interface vlan 5
console(config-if-vlan5)#ip helper-address
192.168.10.1 dhcp
console(config-if-vlan5)#ip helper-address
192.168.20.1 dhcp
To relay both DHCP and DNS packets to 192.168.30.1,
use the following commands:
console#config
console(config)#interface vlan 5
console(config-if-vlan5)#ip helper-address
192.168.30.1 dhcp
console(config-if-vlan5)#ip helper-address
192.168.30.1 dns
713
IP Helper Commands