4000 Router Series Layer 3 - IP Services Configuration Guide

Dynamic IP address assignment configuration example

Network requirements

• As shown in Figure 17, the DHCP server (Router A) assigns IP address to clients on subnet

10 .1.1. 0 / 2 4 , wh i c h i s s u b n e t t e d i n t o 10 .1.1. 0 / 2 5 a n d 10 .1.1.12 8 / 2 5 .

• The IP addresses of Ethernet 1/1 and Ethernet 1/2 on Router A are 10.1.1.1/25 and 10.1.1.129/25.

• In subnet 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 10.1.1.2/25, the WINS server address is

10.1.1.4/25, and the gateway address is 10.1.1.126/25.

• In the subnet 10.1.1.128/25, the address lease duration is five days, the domain name suffix is

aabbcc.com, the DNS server address is 10.1.1.2/25, and the gateway address is 10.1.1.254/25

and there is no WINS server address.

Figure 17 Network diagram

Configuration procedure

1. Specify IP addresses for interfaces. (Details not shown.)

2. Configure the DHCP server:

# Enable DHCP.

<RouterA> system-view

[RouterA] dhcp enable

# Enable the DHCP server on Ethernet 1/1 and Ethernet 1/2.

[RouterA] interface ethernet 1/1

[RouterA-Ethernet1/1] dhcp select server

[RouterA-Ethernet1/1] quit

[RouterA] interface ethernet 1/2

[RouterA-Ethernet1/2] dhcp select server

[RouterA-Ethernet1/2] quit

# Exclude IP addresses from dynamic allocation (addresses of the DNS server, WINS server, and

gateways).

[RouterA] dhcp server forbidden-ip 10.1.1.2

[RouterA] dhcp server forbidden-ip 10.1.1.4

[RouterA] dhcp server forbidden-ip 10.1.1.126

[RouterA] dhcp server forbidden-ip 10.1.1.254