Dhcp Public Configuration - Huawei Quidway S3500 Series Operation Manual

Operation Manual - Network Protocol
Quidway S3500 Series Ethernet Switches
segments. If the early DHCP is used to dynamically configure the host, each subnet
should be equipped with a DHCP Server, which is obviously uneconomical. The
introduction of DHCP relay solves this difficulty. The DHCP relay serves as relay
between the DHCP Client and the DHCP Server located on different subnets. The
DHCP packets can be relayed to the destination DHCP Server (or Client) across
network segments. Thereby, the DHCP clients on different networks can use the same
DHCP Server. This is economical and convenient for centralized management.
DHCP client
DHCP client
Figure 5-2 DHCP Relay typical application
DHCP Relay work on this principle:
In the startup and DHCP initialization, DHCP Client advertises configuration
request messages to the local network.
If there is a DHCP Server in the local network, you can initiate DHCP configuration
directly, with DHCP Relay unnecessary.
Otherwise, when a device with DHCP Relay enabled which is connected with the
local network receives the messages, it will make necessary processing and
forward them to the designated DHCP Server on other network.
DHCP Server makes configurations according to the information from DHCP
Client and sends the configuration result via DHCP Relay back to DHCP Client.
In practice, several times of interaction behaviors may be required in the dynamic
configuration of DHCP Client.

5.2 DHCP Public Configuration

DHCP public configurations refer to those configurations suitable for both DHCP server
and DHCP Relay. The configuration includes:
Enable/Disable the DHCP service
Define DHCP message handling method
Enable/Disable Pseudo-DHCP server detection
DHCP client
Ethernet
Switch ( DHCP Relay)
DHCP client
Huawei Technologies Proprietary
5-4
Chapter 5 DHCP Configuration
Internet
DHCP Server