312
EES4710BD 10 Slots L2/L3/L4 Chassis Switch
Scenario 2:
Fig 14-3 DHCP Relay Configuration
As shown in the above figure, ES4710BD is configured as a DHCP relay. The DHCP server address
is 10.1.1.10, TFTP server address is 10.1.1.20, the configuration steps are 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)#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 67
Switch(Config)#interface vlan 1
Switch(Config-If-Vlan1)#ip help-address 10.1.1.10
Switch(Config-If-Vlan1)#exit
Switch(Config)#ip forward-protocol udp 69
Switch(Config)#interface vlan 1
Switch(Config-If-Vlan1)#ip help-address 10.1.1.20
Note: DHCP server address and TFTP server address must be configured separately since their
receiving UDP protocols are different. 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.
Usage Guide:
When a DHCP/BootP client is connected to a VLAN1 port of the switch, the client can only get its
address from 10.16.1.0/24 instead of 10.16.2.0/24. This is because the broadcast packet from the