Dynamic IP address assignment configuration example
Network requirements
As shown in Figure 21, the DHCP server (Router A) assigns IP addresses to clients on subnet 10.1.1.0/24, which is subnetted into 10.1.1.0/25 and 10.1.1.128/25.
Configure DHCP server on Router A to implement the following assignment scheme.
Table 3: Assignment scheme
DHCP clients | IP address | Lease | Other configuration parameters |
|---|---|---|---|
Clients that connect to GigabitEthernet 1/0/1 | IP addresses on subnet 10.1.1.0/25 | 10 days and 12 hours |
|
Clients that connect to GigabitEthernet 1/0/2 | IP addresses on subnet 10.1.1.128/25 | Five days |
|
Figure 21: Network diagram
Configuration procedure
Specify IP addresses for interfaces. (Details not shown.)
Configure the DHCP server:
# Enable DHCP.
<RouterA> system-view [RouterA] dhcp enable
# Enable the DHCP server on GigabitEthernet 1/0/1 and GigabitEthernet 1/0/2.
[RouterA] interface gigabitethernet 1/0/1 [RouterA-GigabitEthernet1/0/1] dhcp select server [RouterA-GigabitEthernet1/0/1] quit [RouterA] interface gigabitethernet 1/0/2 [RouterA-GigabitEthernet1/0/2] dhcp select server [RouterA-GigabitEthernet1/0/2] quit
# Exclude addresses of the DNS server, WINS server, and gateways from dynamic allocation.
[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
# Configure DHCP address pool 1 to assign IP addresses and other configuration parameters to clients on subnet 10.1.1.0/25.
[RouterA] dhcp server ip-pool 1 [RouterA-dhcp-pool-1] network 10.1.1.0 mask 255.255.255.128 [RouterA-dhcp-pool-1] expired day 10 hour 12 [RouterA-dhcp-pool-1] domain-name aabbcc.com [RouterA-dhcp-pool-1] dns-list 10.1.1.2 [RouterA-dhcp-pool-1] gateway-list 10.1.1.126 [RouterA-dhcp-pool-1] nbns-list 10.1.1.4 [RouterA-dhcp-pool-1] quit
# Configure DHCP address pool 2 to assign IP addresses and other configuration parameters to clients on subnet 10.1.1.128/25.
[RouterA] dhcp server ip-pool 2 [RouterA-dhcp-pool-2] network 10.1.1.128 mask 255.255.255.128 [RouterA-dhcp-pool-2] expired day 5 [RouterA-dhcp-pool-2] domain-name aabbcc.com [RouterA-dhcp-pool-2] dns-list 10.1.1.2 [RouterA-dhcp-pool-2] gateway-list 10.1.1.254 [RouterA-dhcp-pool-2] quit
Verifying the configuration
# Verify that clients on subnets 10.1.1.0/25 and 10.1.1.128/25 can obtain correct IP addresses and all other network parameters from Router A. (Details not shown.)
# On the DHCP server, display the IP addresses assigned to the clients.
[RouterA] display dhcp server ip-in-use
IP address Client identifier/ Lease expiration Type
Hardware address
10.1.1.3 0031-3865-392e-6262- Jan 14 22:25:03 2015 Auto(C)
3363-2e30-3230-352d-
4745-302f-30
10.1.1.5 0031-fe65-4203-7e02- Jan 14 22:25:03 2015 Auto(C)
3063-5b30-3230-4702-
620e-712f-5e
10.1.1.130 3030-3030-2e30-3030- Jan 9 10:45:11 2015 Auto(C)
662e-3030-3033-2d45-
7568-6572-1e
10.1.1.131 3030-0020-fe02-3020- Jan 9 10:45:11 2015 Auto(C)
7052-0201-2013-1e02
0201-9068-23
10.1.1.132 2020-1220-1102-3021- Jan 9 10:45:11 2015 Auto(C)
7e52-0211-2025-3402
0201-9068-9a
10.1.1.133 2021-d012-0202-4221- Jan 9 10:45:11 2015 Auto(C)
8852-0203-2022-55e0
3921-0104-31