Configuring Option 82 Support On The Dhcp Relay - 3Com 3C13636 Configuration Manual

3Com Router 3000 Ethernet Family
Configuration Guide
Table 9-44 Release client IP address from DHCP relay
Requests
release client IP address
Requests a specific DHCP server
to release client IP address
If no DHCP server is specified, in system view, the release request will be sent to all
DHCP servers; while in interface view, the release request will be sent to the current
interface.
Note:
After receiving an IP address release request from the DHCP relay, the DHCP server
releases the IP address from the IP-in-use address pool and moves it to the
lease-expired queue. Normally, this address will experience some time before
participating in allocation again. For the client, however, this address is not released
and will be used until its lease really expires.
Release packets take effect only when the server uses MAC addresses to identify
users. When the DHCP server function is deployed on a router, you can use the
display dhcp server ip-in-use command to display the related information. If the
words "Hardware address" are displayed, the server is using MAC addresses to identify
users; if the words "Client identifier/Hardware address" are displayed, the server is
using client identifiers to identify users.

9.6.5 Configuring Option 82 Support on the DHCP Relay

I. Configuration prerequisites
Before configuring option 82 support on the DHCP relay, make sure that:
The DHCP relay function is enabled on your device and the network parameters of
the device are configured.
The network parameters, and address pool and address lease allocation policies
are configured for the DHCP relay.
The DHCP relay device is reachable.
For more information, refer to the part discussing DHCP.
Operation
DHCP server to
3Com Corporation
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Chapter 9 DHCP Configuration
Command
dhcp relay release client-ip mac-address
dhcp relay release client-ip mac-address
server-ip