2-24 
z  After sending a DHCP-ACK packet with the IP configuration parameters to the DHCP client, the 
DHCP server sends an Accounting START packet to a specified RADIUS server. The RADIUS 
server processes the packet, makes a record, and sends a response to the DHCP server. 
z  Once releasing a lease, the DHCP server sends an Accounting STOP packet to the RADIUS 
server. The RADIUS server processes the packet, stops the recording for the DHCP client, and 
sends a response to the DHCP server. A lease can be released for the reasons such as lease 
expiration, a release request received from the DHCP client, a manual release operation, an 
address pool removal operation. 
 
 
If the RADIUS server of the specified domain is unreachable, the DHCP server sends up to three 
Accounting START packets (including the first sending attempt) at regular intervals. If the three packets 
bring no response from the RADIUS server, the DHCP server does not send Accounting START 
packets any more. 
 
DHCP Accounting Configuration 
Prerequisites 
Before configuring DHCP accounting, make sure that: 
z  The DHCP server is configured and operates properly. Address pools and lease time are 
configured. 
z  DHCP clients are configured and DHCP service is enabled. 
z  The network operates properly. 
Configuring DHCP Accounting 
Follow these steps to configure DHCP accounting: 
To do…  Use the command…  Remarks 
Enter system view 
system-view 
— 
Enter address pool view 
dhcp server ip-pool 
pool-name 
Required 
Enable DHCP accounting 
accounting domain 
domain-name 
Required 
The domain identified by the 
domain-name argument can be 
created by using the domain 
command. 
 
Enabling the DHCP Server to Process Option 82 
If a DHCP server is enabled to process Option 82, after the DHCP server receives packets containing 
Option 82, the DHCP server adds Option 82 into the responses when assigning IP addresses and other 
configuration information to the clients.