Option 82 Configuration Example; Troubleshooting Dhcp Relay Agent Configuration; Symptom; Analysis - HP 5920 Series Configuration Manual

[SwitchA-Vlan-interface10] dhcp select relay
# Specify the IP address of the DHCP server on the relay agent.
[SwitchA-Vlan-interface10] dhcp relay server-address 10.1.1.1
After the preceding configuration is complete, DHCP clients can obtain IP addresses and other network
parameters from the DHCP server through the DHCP relay agent. You can use the display dhcp relay
statistics command to view the statistics of DHCP packets forwarded by the DHCP relay agent. If you
enable relay entry record on the DHCP relay agent with the dhcp relay client-information record
command, you can use the display dhcp relay client-information command to view relay entries.

Option 82 configuration example

Network requirements
As shown in
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.
<SwitchA> 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.
Figure 22, the DHCP relay agent (Switch A) replaces Option 82 in DHCP requests before
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