H3C LS-3100-52P-OVS-H3 Operation Manual - page 400
3-10
Figure 3-3 Network diagram for DHCP relay agent
Switch B
DHCP server
Switch A
DHCP relay agent
DHCP client
DHCP client
DHCP client
DHCP client
Vlan-int2
10.1.1.2/24
Vlan-int1
10.10.1.1/24
Vlan-int2
10.1.1.1/24
Configuration procedure
# Specify IP addresses for the interfaces (omitted).
# Enable DHCP.
[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
z
Performing the configuration on the DHCP server is also required to guarantee the client-server
communication via the relay agent. Refer to
DHCP Server Configuration Examples
for DHCP
server configuration information.
z
Because the DHCP relay agent and server are on different subnets, you need to configure a static
route or dynamic routing protocol to make them reachable to each other.
DHCP Relay Agent Option 82 Support Configuration Example
Network requirements
z
As shown in
Figure 3-3
, Enable Option 82 on the DHCP relay agent (Switch A).
z
Configure the handling strategy for DHCP requests containing Option 82 as replace.
z
Configure the padding content for the circuit ID sub-option as company001 and for the remote ID
sub-option as device001.