Users Guide

Table Of Contents
1260 Layer-2 and Layer-3 Relay Features
Relay Agent Configuration Example
The example in this section shows how to configure the L3 relay agent (IP
helper) to relay and discard various protocols.
Figure 33-13. L3 Relay Network Diagram
This example assumes that multiple VLAN routing interfaces have been
created, and configured with IP addresses.
To configure the switch:
1
Relay DHCP packets received on VLAN 10 to 192.168.40.35
console#config
console(config)#interface vlan 10
console(config-if-vlan10)#ip helper-address 192.168.40.35 dhcp
2
Relay DNS packets received on VLAN 10 to 192.168.40.43
VLAN 30
` `
`
`
DHCP Server
192.168.40.35
DHCP Clients
VLAN 10
L3 Switch
VLAN 20 (No DHCP)
DHCP Server
192.168.40.22
SNMP Server
192.168.23.1
DNS Server
192.168.40.43