Adding Global Dhcp Address Pool - 3Com 3C13636 Configuration Manual

3Com Router 3000 Ethernet Family
Configuration Guide
Note:
To use interface address pools for address allocation, you must configure the dhcp
select interface command.
You may configure the subaddress keyword to allow the DHCP server to assign a
DHCP client an IP address belonging to a subaddress segment for the Ethernet
interface. This IP address is selected from the global address pool corresponding to the
subaddress segment. When subaddress allocation is enabled, the Ethernet interface
on the DHCP server must be assigned a subaddress located in the subaddress
segment from which subaddresses are selected for DHCP clients. This is to ensure that
the main address and the IP address assigned to a DHCP client are located in different
network segments.

9.5.2 Adding Global DHCP Address Pool

DHCP server allocates IP addresses from the address pool. When DHCP client
originates DHCP requests to DHCP server, the server will choose a proper address
pool according to a certain algorithm and select a free IP address, which, along with
other parameters (for example DNS IP address, address lease limit), is sent to the
client. With V 2.41, a DHCP server by far can be configured with 128 global address
pools.
The address pools in DHCP server is in tree structure: the native segment address as
root, sub-net addresses as branch, addresses bound to the clients as leaf nodes. This
structure guarantees configuration inheritance: the sub-net (son node) inherits the
configurations of the native segment (father node); the client (grandson node) inherits
the configurations of the sub-net. For those common parameters, for example domain
name, you can just configure them at the native segment or sub-net. You can view the
structure of the address pools with the display dhcp server tree command. The order
for those address pools at the same level is defined by creation time.
Perform the following configurations in the system view.
Table 9-5 Add global DHCP address pool
Adds DHCP address pool or enter
DHCP address pool view
Deletes DHCP address pool
By default, no global DHCP address pool is created.
Operation
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Chapter 9 DHCP Configuration
Command
dhcp server ip-pool pool-name
undo dhcp server ip-pool pool-name