H3C Technologies H3C S12500-X Series Switches - Manual (Page 46)

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Step Command Remarks
9. (Optional.) Exclude the specified
IP addresses from dynamic
allocation globally.
dhcp server forbidden-ip
start-ip-address [ end-ip-address ]
Except for the IP address of
the DHCP server interface, IP
addresses in all address pools
are assignable by default.
To exclude multiple address
ranges globally, repeat this
step.
Configuring a static binding in a DHCP address pool
Some DHCP clients, such as a WWW server, need fixed IP addresses. To provide a fixed IP address for
such a client, you can statically bind the MAC address or ID of the client to an IP address in a DHCP
address pool. When the client requests an IP address, the DHCP server assigns the IP address in the static
binding to the client.
Follow these guidelines when you configure a static binding:
• One IP address can be bound to only one client MAC or client ID. You cannot modify bindings that
have been created. To change the binding for a DHCP client, you must delete the existing binding
first.
• The IP address of a static binding cannot be the address of the DHCP server interface. Otherwise,
an IP address conflict occurs and the bound client cannot obtain an IP address correctly.
• To configure static bindings for DHCP clients that reside on the same device and use the same MAC
address, you must specify the client ID rather than the MAC address to identify a requesting
interface. Otherwise, IP address allocation will fail.
To configure a static binding:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter address pool view. dhcp server ip-pool pool-name N/A
3. Configure a static binding.
static-bind ip-address ip-address
[ mask-length | mask mask ]
{ client-identifier client-identifier |
hardware-address
hardware-address [ ethernet |
token-ring ] }
By default, no static binding is
configured.
To add more static bindings,
repeat this step.
4. (Optional.) Specify the lease
duration for the IP address.
expired { day day [ hour hour
[ minute minute [ second second ] ] ]
| unlimited }
The default setting is 1 day.
Specifying gateways for the client
DHCP clients send packets destined for other networks to a gateway. The DHCP server can assign the
gateway address to the DHCP clients.
You can specify gateway addresses in each address pool on the DHCP server. A maximum of eight
gateways can be specified in DHCP address pool view or secondary subnet view.