H3C Technologies H3C S5560 Series Switches - Manual (Page 77)

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Verifying the configuration
# Verify that DHCP clients can obtain IP addresses and all other network parameters from the DHCP
server through the DHCP relay agent. (Details not shown.)
# Display the statistics of DHCP packets forwarded by the DHCP relay agent.
[SwitchA] display dhcp relay statistics
# Display relay entries if you have enabled relay entry recording on the DHCP relay agent.
[SwitchA] display dhcp relay client-information
Option 82 configuration example
Network requirements
As shown in Figure 23 , the DHCP relay agent (Switch A) replaces Option 82 in DHCP requests before
forwarding them to the DHCP server (Switch B).
• The Circuit ID sub-option is company001.
• The Remote ID sub-option is device001.
To use Option 82, you must also enable the DHCP server to handle Option 82.
Configuration procedure
# Specify IP addresses for the interfaces. (Details not shown.)
# Enable DHCP.
system-view
[SwitchA] dhcp enable
# Enable the DHCP relay agent on VLAN-interface 10.
[SwitchA] interface vlan-interface 10
[SwitchA-Vlan-interface10] dhcp select relay
# Specify the IP address of the DHCP server.
[SwitchA-Vlan-interface10] dhcp relay server-address 10.1.1.1
# Configure the handling strategies and padding content of Option 82.
[SwitchA-Vlan-interface10] dhcp relay information enable
[SwitchA-Vlan-interface10] dhcp relay information strategy replace
[SwitchA-Vlan-interface10] dhcp relay information circuit-id string company001
[SwitchA-Vlan-interface10] dhcp relay information remote-id string device001
Troubleshooting DHCP relay agent configuration
Symptom
DHCP clients cannot obtain configuration parameters through the DHCP relay agent.
Analysis
Some problems might occur with the DHCP relay agent or server configuration.