3com 4210 Manual De Usuario

In general, there are two typical DHCP network topologies. One is to deploy the 
DHCP server and DHCP clients in the same network segment. This enables the 
clients to communicate with the server directly. The other is to deploy the DHCP 
server and DHCP clients in different network segments. In this case, IP address 
assignment is carried out through a DHCP relay agent. Note that the DHCP server 
configuration is the same in both scenarios.

Figure 53   Network diagram for DHCP server global address pool configuration

 

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The DHCP server (Switch A) assigns IP addresses to clients in subnet 
10.1.1.0/24, which is subnetted into 10.1.1.0/25 and 10.1.1.128/25.

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The IP addresses of VLAN-interface 1 and VLAN-interface 2 on Switch A are 
10.1.1.1/25 and 10.1.1.129/25 respectively.

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In the address pool 10.1.1.0/25, the address lease duration is ten days and 
twelve hours, the domain name suffix is aabbcc.com, the DNS server address is 
10.1.1.2, the WINS server address is 10.1.1.4, and the gateway address is 
10.1.1.126.

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In the address pool 10.1.1.128/25, the address lease duration is five days, the 
domain name suffix is aabbcc.com, the DNS server address is 10.1.1.2, and the 
gateway address is 10.1.1.254; there is no WINS server address.

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Enable unauthorized DHCP server detection on Switch A so that the 
administrator can check out any unauthorized DHCP servers from the system 
log information.

10.1.1.4 /25

Switch B

10 .1.1.2/25

Switch A

Vlan -int2
10.1.1.129/25

Vlan -int1

10.1.1 .1/25

Vlan-int1

10.1 .1.126 /25

10 .1 .1.254 /25