420
To do…
Command…
Remarks
4.
Enable authorized ARP on the
interface.
arp authorized enable
Required.
Not enabled by default.
With
arp authorized enable
executed, an
interface of a DHCP server (or a DHCP
relay agent) that does not support
authorized ARP is disabled from
dynamically learning ARP entries and
cannot generate authorized ARP entries.
5.
Configure the aging time for
authorized ARP entries.
arp authorized time-out
seconds
Optional.
1200 seconds by default.
Authorized ARP on DHCP server configuration example
Network requirements
As shown in
, Router A acts as a DHCP server with an IP address pool of 10.1.1.0/24.
Enable authorized ARP on GigabitEthernet1/0/1 of Router A to start aging detection. Router B is a
DHCP client that obtains an IP address of 10.1.1.2/24 from the DHCP server.
Figure 145
Network diagram for authorized ARP configuration
Configuration procedure
1.
Configure Router A.
# Configure the IP address of GigabitEthernet1/0/1.
<RouterA> system-view
[RouterA] interface gigabitethernet1/0/1
[RouterA-GigabitEthernet1/0/1] ip address 10.1.1.1 24
[RouterA-GigabitEthernet1/0/1] quit
# Configure DHCP.
[RouterA] dhcp enable
[RouterA] dhcp server ip-pool 1
[RouterA-dhcp-pool-1] network 10.1.1.0 mask 255.255.255.0
[RouterA-dhcp-pool-1] quit
# Enter Layer 3 Ethernet interface view.
[RouterA] interface gigabitethernet1/0/1