H3C Technologies H3C WX3000 Series Unified Switches - Manual (Page 313)

31-9
Figure 33-4 Network diagram for DHCP relay agent
Switch B
DHCP server
Switch A
DHCP relay
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
# Create DHCP server group 1 and configure an IP address of 10.1.1.1 for it.
<SwitchA> system-view
[SwitchA] dhcp-server 1 ip 10.1.1.1
# Map VLAN-interface 1 to DHCP server group 1.
[SwitchA] interface vlan-interface 1
[SwitchA-Vlan-interface1] dhcp-server 1
z
You need to perform corresponding configurations on the DHCP server to enable the DHCP clients
to obtain IP addresses from the DHCP server. The DHCP server configurations vary with different
DHCP server devices, so the configurations are omitted.
z
The DHCP relay agent and DHCP server must be reachable to each other.
Troubleshooting DHCP Relay Agent Configuration
Symptom
A client fails to obtain configuration information through a DHCP relay agent.
Analysis
This problem may be caused by improper DHCP relay agent configuration. When a DHCP relay agent
operates improperly, you can locate the problem by enabling debugging and checking the information
about debugging and interface state (You can display the information by executing the corresponding
display command.)
Solution
z
Check if DHCP is enabled on the DHCP server and the DHCP relay agent.
z
Check if an address pool that is on the same network segment with the DHCP clients is configured
on the DHCP server.
z
Check if a reachable route is configured between the DHCP relay agent and the DHCP server.