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DHCP Configuration
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Fig 31-3 DHCP Relay Configuration
As shown in the above figure, route switch is configured as a DHCP relay. The DHCP
server address is 10.1.1.10, the configuration steps is as follows:
Switch(config)#service dhcp
Switch(config)#interface vlan 1
Switch(Config-if-Vlan1)#ip address 192.168.1.1 255.255.255.0
Switch(Config-if-Vlan1)#exit
Switch(config)#vlan 2
Switch(Config-Vlan-2)#exit
Switch(config)#interface Ethernet 1/0/2
Switch(Config-Erthernet1/0/2)#switchport access vlan 2
Switch(Config-Erthernet1/0/2)#exit
Switch(config)#interface vlan 2
Switch(Config-if-Vlan2)#ip address 10.1.1.1 255.255.255.0
Switch(Config-if-Vlan2)#exit
Switch(config)#ip forward-protocol udp bootps
Switch(config)#interface vlan 1
Switch(Config-if-Vlan1)#ip help-address 10.1.1.10
Switch(Config-if-Vlan1)#exit
Note: It is recommended to use the combination of command
ip forward-protocol udp
<port>
and
ip helper-address
<ipaddress>
.
ip help-address
can only be configured for
ports on layer 3 and cannot be configured on layer 2 ports directly.
DHCP Server
10.1.1.10
DHCP Client
DHCP Client
DHCP Client
E1/0/1
192.168.1.1
DHCP Relay
E1/0/2
10.1.1.1