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DHCP relay agent configuration commands
NOTE:
The DHCP relay agent configuration is supported only on VLAN interfaces.
dhcp relay address-check
Syntax
dhcp relay address-check
{
disable
|
enable
}
View
Interface view
Default level
2: System level
Parameters
disable
: Disables address check on the relay agent.
enable
: Enables address check on the relay agent.
Description
Use the
dhcp relay address-check enable
command to enable address check on the relay agent.
Use the
dhcp relay address-check disable
command 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 VLAN interfaces.
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 vlan-interface 1
[Sysname-Vlan-interface1] dhcp relay address-check enable