Dhcp Server Configuration; Introduction To Dhcp Server; Application Environment; Dhcp Address Pool - HP A5120 EI Series Configuration Manual

DHCP server configuration

NOTE:
The DHCP server configuration is supported only on VLAN interfaces, and loopback interfaces. The
secondary IP address pool configuration is not supported on loopback interfaces.

Introduction to DHCP server

Application environment

The DHCP server is well suited to networks where:
 Manual configuration and centralized management are difficult to implement.
 Many hosts need to acquire IP addresses dynamically. This may be because the number of hosts
exceeds the number of assignable IP addresses, so it is impossible to assign a fixed IP address to
each host. For example, an ISP has a limited number of host addresses.
A few hosts need fixed IP addresses.


DHCP address pool

Address pool types
DHCP address pools include common and extended address pools.
Common address pool: Supports both static binding and dynamic allocation.

Extended address pool: Supports only dynamic allocation.

Common address pool structure
The common address pool database is organized as a tree. The root of the tree is the address pool for
natural networks, branches are address pools for subnets, and leaves are addresses statically bound to
clients. For the same level address pools, a previously configured pool has a higher selection priority than
a new one.
At the very beginning, subnets inherit network parameters and clients inherit subnetwork parameters.
Therefore, common parameters, for example a DNS server address, should be configured at the highest
(network or subnet) level of the tree.
The new configuration at the higher level (parent) of the tree will be:
Inherited if the lower level (child) has no such configuration, or

Overridden if the lower level (child) has such configuration.

NOTE:

The extended address pools on a DHCP server are independent of each other and no inheritance relationship
exists among them..

IP address lease durations are not inherited.
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