3com 3031 Instruccion De Instalación

If there is a DHCP server in the network, it begins DHCP configurations without 
DHCP relay. 

If not, the local network processes the packet and forwards it to the specified 
DHCP server in another sub-net.

The DHCP server undertakes configurations according to the information from the 
client and sends the configuration information through DHCP relay back to the 
client. Till now, dynamic configuration for the client ends is completed. In practice, 
multiple message exchange processes may be required to finish client 
configuration. 

It can be seen that DHCP relay supports transparent transmission of DHCP 
broadcast messages and can transmit broadcast messages from DHCP client (or 
server) transparently to the DHCP server (or client) in another sub-net. 

In real network, DHCP relay function is often implemented at a specific interface 
of a router. So you should configure IP relay address for the interface to specify a 
target DHCP server. 

DHCP common configurations refer to those configurations suitable for both 
DHCP server and DHCP relay. The configuration tasks include

■

Enable/Disable DHCP services

■

Defining DHCP message processing mode

■

Configuring pseudo-DHCP server detection

For both DHCP server and DHCP relay, you must first enable DHCP services before 
starting DHCP configurations. 

Perform the following in the System View. 

By default, the DHCP services are enabled. 

With proper configurations, you can decide how to process those DHCP messages 
sent to the host by client. 

Perform the following in the Interface View to define DHCP message processing 
mode at the current interface.

Table 414   Enabling/Disabling DHCP services

Enable DHCP services

Disable DHCP services

Table 415   Defining DHCP message processing mode at the current interface

Sends DHCP messages to local DHCP server and allocates 
address from the global address pool