R3721-F3210-F3171-HP High-End Firewalls Network Management Command Reference-6PW101

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DHCP relay agent configuration commands
NOTE:
The DHCP relay agent configuration is supported only on Layer 3 Ethernet interfaces (or subinterfaces)
and Layer 3 aggregate interfaces.
dhcp relay address-check enable
Syntax
dhcp relay address-check enable
undo dhcp relay address-check enable
View
Interface view
Default level
2: System level
Parameters
None
Description
Use dhcp relay address-check enable to enable address check on the relay agent.
Use undo dhcp relay address-check enable to disable address check on the relay agent.
By default, the function is disabled.
With this feature enabled, the DHCP relay agent can dynamically record clients' IP-to-MAC bindings
after clients get IP addresses through DHCP. It also supports static bindings. You can manually configure
IP-to-MAC bindings on the DHCP relay agent, so that users can access external networks using fixed IP
addresses.
Upon receiving an ARP packet, the DHCP relay agent matches the sender's IP and MAC addresses in the
packet against the bindings (both dynamic and static). If no match is found, the DHCP relay agent does
not learn the ARP entry. The sending host cannot access external networks via the DHCP relay agent.
This command can be executed only on Layer 3 Ethernet interfaces (including subinterfaces).
The dhcp relay address-check enable command only checks IP and MAC addresses of clients.
Examples
# Enable address check on the DHCP relay agent.
<Sysname> system-view
[Sysname] interface GigabitEthernet 0/1
[Sysname-GigabitEthernet0/1] dhcp relay address-check enable