H3C Technologies H3C S5120 Series Switches - Manual (Page 249)

1-9
DHCP Relay Agent Configuration Examples
DHCP Relay Agent Configuration Example
Network requirements
As shown in Figure 1-3 , DHCP clients reside on network 10.10.1.0/24. The IP address of the DHCP
server is 10.1.1.1/24. Because the DHCP clients reside on a different network with the DHCP server, a
DHCP relay agent is deployed to forward messages between DHCP clients and the DHCP server.
VLAN-interface 1 on the DHCP relay agent (Switch A) connects to the network where DHCP clients
reside. The IP address of VLAN-interface 1 is 10.10.1.1/24 and the IP address of VLAN-interface 2 is
10.1.1.2/24.
Figure 1-3 Network diagram for DHCP relay agent
Configuration procedure
# Specify IP addresses for the interfaces (omitted).
# Enable DHCP.
<SwitchA> system-view
[SwitchA] dhcp enable
# Add DHCP server 10.1.1.1 into DHCP server group 1.
[SwitchA] dhcp relay server-group 1 ip 10.1.1.1
# Enable the DHCP relay agent on VLAN-interface 1.
[SwitchA] interface vlan-interface 1
[SwitchA-Vlan-interface1] dhcp select relay
# Correlate VLAN-interface 1 to DHCP server group 1.
[SwitchA-Vlan-interface1] dhcp relay server-select 1
After the preceding configuration is complete, DHCP clients can obtain IP addresses and other network
parameters through the DHCP relay agent from the DHCP server. You can use the display dhcp relay
security command to view bindings of DHCP relay agents, and use the display dhcp relay statistics
command to view statistics of DHCP packets forwarded by DHCP relay agents.