127
Procedure
# Enable DHCP.
<RouterA> system-view
[RouterA] dhcp enable
# Configure the primary and secondary IP addresses of GigabitEthernet1/0/1, and enable the DHCP
server on GigabitEthernet 1/0/1.
[RouterA] interface gigabitethernet 1/0/1
[RouterA-GigabitEthernet1/0/1] ip address 10.1.1.1 24
[RouterA-GigabitEthernet1/0/1] ip address 10.1.2.1 24 sub
[RouterA-GigabitEthernet1/0/1] dhcp select server
[RouterA-GigabitEthernet1/0/1] quit
# Create DHCP address pool
aa
.
[RouterA] dhcp server ip-pool aa
# Specify the primary subnet and the gateway address for dynamic allocation.
[RouterA-dhcp-pool-aa] network 10.1.1.0 mask 255.255.255.0
[RouterA-dhcp-pool-aa] gateway-list 10.1.1.254
# Specify the secondary subnet and the gateway address for dynamic allocation.
[RouterA-dhcp-pool-aa] network 10.1.2.0 mask 255.255.255.0 secondary
[RouterA-dhcp-pool-aa-secondary] gateway-list 10.1.2.254
[RouterA-dhcp-pool-aa-secondary] quit
[RouterA-dhcp-pool-aa] quit
Verifying the configuration
# Verify that the DHCP server assigns clients IP addresses and gateway address from the secondary
subnet when no assignable address is available from the primary subnet. (Details not shown.)
# On the DHCP server, display IP addresses assigned to the clients. The following is part of the
command output.
[RouterA] display dhcp server ip-in-use
IP address Client identifier/ Lease expiration Type
Hardware address
10.1.1.2 0031-3865-392e-6262- Jan 14 22:25:03 2015 Auto(C)
3363-2e30-3230-352d-
4745-302f-30
10.1.2.2 3030-3030-2e30-3030- Jan 14 22:25:03 2015 Auto(C)
662e-3030-3033-2d45-
7568-6572-1e
Example: Customizing DHCP option
Network configuration
As shown in
, DHCP clients obtain IP addresses and PXE server addresses from the DHCP
server (Router A). The subnet for address allocation is 10.1.1.0/24.
Configure the address allocation scheme as follows:
Assign PXE addresses
To clients
2.3.4.5 and 3.3.3.3
The hardware address in the request is six bytes long and
begins with
aabb-aabb
.
