Configuring Dhcp Accounting Functions; Introduction To Dhcp Accounting; Dhcp Accounting Fundamentals; Dhcp Accounting Configuration - H3C S5600 Series Operation Manual

Operation Manual – DHCP
H3C S5600 Series Ethernet Switches

2.7 Configuring DHCP Accounting Functions

2.7.1 Introduction to DHCP Accounting

DHCP accounting allows a DHCP server to notify the RADIUS server of the start/end of
accounting when it assigns/releases a lease. The cooperation of DHCP server and
RADIUS server implements the network accounting function and ensures network
security at the same time.

2.7.2 DHCP Accounting Fundamentals

After you complete AAA and RADIUS configuration on a switch with the DHCP server
function enabled, the DHCP server acts as a RADIUS client. For the authentication
process of the DHCP server acting as a RADIUS client, refer to AAA Operation in this
manual. The following describes only the accounting interaction between DHCP server
and RADIUS server.
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.
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.
Note:
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.

2.7.3 DHCP Accounting Configuration

I. Prerequisites
Before configuring DHCP accounting, make sure that:
The DHCP server is configured and operates properly. Address pools and lease
time are configured.
DHCP clients are configured and DHCP service is enabled.
Chapter 2 DHCP Server Configuration
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