Example: Configuring authorized ARP on a DHCP server

Network configuration

As shown in Figure 160, configure authorized ARP on HundredGigE 1/0/1 of Device A (a DHCP server) to ensure user validity.

Figure 160: Network diagram

Procedure

  1. Configure Device A:

    # Specify the IP address for HundredGigE 1/0/1.

    <DeviceA> system-view
    [DeviceA] interface hundredgige 1/0/1
    [DeviceA-HundredGigE1/0/1] ip address 10.1.1.1 24
    [DeviceA-HundredGigE1/0/1] quit
    

    # Configure DHCP.

    [DeviceA] dhcp enable
    [DeviceA] dhcp server ip-pool 1
    [DeviceA-dhcp-pool-1] network 10.1.1.0 mask 255.255.255.0
    [DeviceA-dhcp-pool-1] quit
    

    # Enter Layer 3 Ethernet interface view.

    [DeviceA] interface hundredgige 1/0/1
    

    # Enable authorized ARP.

    [DeviceA-HundredGigE1/0/1] arp authorized enable
    [DeviceA-HundredGigE1/0/1] quit
    
  2. Configure Device B:

    <DeviceB> system-view
    [DeviceB] interface hundredgige 1/0/1
    [DeviceB-HundredGigE1/0/1] ip address dhcp-alloc
    [DeviceB-HundredGigE1/0/1] quit
    

Verifying the configuration

# Display authorized ARP entry information on Device A.

[DeviceA] display arp all
  Type: S-Static   D-Dynamic   O-Openflow   R-Rule   M-Multiport  I-Invalid
IP Address       MAC Address    SVLAN/VSI Interface/Link ID        Aging Type
10.1.1.2         0012-3f86-e94c N/A       HGE1/0/1                 960   D

The output shows that IP address 10.1.1.2 has been assigned to Device B.

Device B must use the IP address and MAC address in the authorized ARP entry to communicate with Device A. Otherwise, the communication fails. Thus user validity is ensured.