3Com 4500 PWR 26-Port Configuration Manual page 481

In the address pool 10.1.1.0/25, the address lease duration is ten days and twelve hours, domain
name suffix aabbcc.com, DNS server address 10.1.1.2, gateway 10.1.1.126, and WINS server
10.1.1.4.
In the address pool 10.1.1.128/25, the address lease duration is five days, domain name suffix
aabbcc.com, DNS server address 10.1.1.2, and gateway address 10.1.1.254, and there is no
WINS server address.
If you use the inheriting relation of parent and child address pools, make sure that the number of the
assigned IP addresses does not exceed the number of the IP addresses in the child address pool;
otherwise extra IP addresses will be obtained from the parent address pool, and the attributes (for
example, gateway) also are based on the configuration of the parent address pool.
For example, in the network to which VLAN-interface 1 is connected, if multiple clients apply for IP
addresses, the child address pool 10.1.1.0/25 assigns IP addresses first. When the IP addresses in the
child address pool have been assigned, if other clients need IP addresses, the IP addresses will be
assigned from the parent address pool 10.1.1.0/24 and the attributes will be based on the configuration
of the parent address pool.
For this example, the number of clients applying for IP addresses from VLAN-interface 1 is
recommended to be less than or equal to 122 and the number of clients applying for IP addresses from
VLAN-interface 2 is recommended to be less than or equal to 124.
Network diagram
Figure 39-1 Network diagram for DHCP configuration
Configuration procedure
1) Configure a VLAN and add a port in this VLAN, and then configure the IP address of the VLAN
interface (omitted).
2) Configure DHCP service.
# Enable DHCP.
<SwitchA> system-view
[SwitchA] dhcp enable
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