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Dynamic Host Configuration Protocol
(DHCP)
The Aggregator is auto-configured to operate as a dynamic host configuration protocol (DHCP) client. The DHCP server, DHCP
relay agent, and secure DHCP features are not supported. The DHCP is an application layer protocol that dynamically assigns
IP addresses and other configuration parameters to network end-stations (hosts) based on configuration policies determined by
network administrators.
DHCP relieves network administrators of manually configuring hosts, which can be a tedious and error-prone process when
hosts often join, leave, and change locations on the network and it reclaims IP addresses that are no longer in use to prevent
address exhaustion.
DHCP is based on a client-server model. A host discovers the DHCP server and requests an IP address, and the server either
leases or permanently assigns one. There are three types of devices that are involved in DHCP negotiation:
DHCP Server This is a network device offering configuration parameters to the client.
DHCP Client This is a network device requesting configuration parameters from the server.
Relay Agent This is an intermediary network device that passes DHCP messages between the client and server when
the server is not on the same subnet as the host.
NOTE: The DHCP server and relay agent features are not supported on an Aggregator.
Supported Modes
Stacking, PMUX, Standalone, VLT
Topics:
Assigning an IP Address using DHCP
Debugging DHCP Client Operation
DHCP Client
How DHCP Client is Implemented
DHCP Client on a Management Interface
DHCP Client on a VLAN
DHCP Packet Format and Options
Option 82
DHCPv6 relay agent options
Releasing and Renewing DHCP-based IP Addresses
Viewing DHCP Statistics and Lease Information
Configuring DHCP relay source interface
DHCP Snooping
Assigning an IP Address using DHCP
The following section describes DHCP and the client in a network.
When a client joins a network:
1. The client initially broadcasts a DHCPDISCOVER message on the subnet to discover available DHCP servers. This message
includes the parameters that the client requires and might include suggested values for those parameters.
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