Logging Out Dhcp Local Server Subscribers - Juniper JUNOSE SOFTWARE FOR E SERIES 11.3.X - BROADBAND ACCESS CONFIGURATION GUIDE 2010-10-12 Configuration Manual

Logging Out DHCP Local Server Subscribers

Copyright © 2010, Juniper Networks, Inc.
Location of DHCP Clients with
Identical IDs or Addresses
On the same subinterface in the
same subnet
In the optional configuration, you use the ip dhcp-local unique-client-ids command to
disable the use of the DHCP client's subnet or subinterface to differentiate between
clients with duplicate client IDs or hardware addresses. When DHCP receives the request
from a duplicate ID or address, DHCP terminates the address lease for the existing client
and returns the address to its original address pool. DHCP then assigns a new address
and lease to the new client.
We strongly recommend that you enable the ip dhcp-local unique-client-ids command
in the following situations:
When duplicate client IDs and duplicate hardware addresses do not exist in your
network
When the DHCP local server application interacts with DHCP relays in your network
that do not support duplicate client IDs or duplicate hardware addresses
Enabling the ip dhcp-local unique-client-ids command in these cases enables you to
properly manage DHCP clients that roam to different subnets.
The DHCP relay agent application and the DHCP relay proxy application do not support
duplicate client IDs or duplicate hardware addresses.
You can use the logout subscribers command from Privileged Exec mode to log out
DHCP local server subscribers. For example, you might use this feature if you want to
force a user to request a new lease or if you want to recover functional resources. The
logout subscribers command, unlike the clear ip address binding command (described
in "Clearing an IP DHCP Local Server Binding" on page 478), does not terminate the
subscriber's user session or management representation.
This command applies to DHCP local server local-access and standalone clients, as well
as to PPP users. You can log out all subscribers, or log out subscribers by username,
domain, virtual-router, or port.
Chapter 19: Configuring DHCP Local Server
How DHCP Local Server Differentiates
Clients
DHCP local server cannot distinguish clients
with identical IDs or identical hardware
addresses in this configuration
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