23
Parameters
None
Description
Use the
dhcp server detect
command to enable unauthorized DHCP server detection.
Use the
undo dhcp server detect
command to disable the function.
By default, the function is disabled.
With this function enabled, upon receiving a DHCP request, the DHCP server will resolve from the request
the IP addresses of DHCP servers which ever offered IP addresses to the DHCP client and the receiving
interface. Each server detected is recorded only once. The administrator can get this information from
logs to check out unauthorized DHCP servers.
Examples
# Enable unauthorized DHCP server detection.
<Sysname> system-view
[Sysname] dhcp server detect
dhcp server forbidden-ip
Syntax
dhcp server forbidden-ip
low-ip-address
[
high-ip-address
]
undo dhcp server forbidden-ip
low-ip-address
[
high-ip-address
]
View
System view
Default level
2: System level
Parameters
low-ip-address
: Specifies the start IP address of the IP address range to be excluded from dynamic
allocation.
high-ip-address
: Specifies the end IP address of the IP address range to be excluded from dynamic
allocation. The end IP address must have a higher sequence than the start one.
Description
Use the
dhcp server forbidden-ip
command to exclude IP addresses from dynamic allocation.
Use the
undo dhcp server forbidden-ip
command to remove the configuration.
By default, all IP addresses in a DHCP address pool are assignable except IP addresses of the DHCP
server interfaces.
When you use the
dhcp server forbidden-ip
command to exclude an IP address that is bound to a user
from dynamic assignment, the address can be still assigned to the user.
When you use the
undo dhcp server forbidden-ip
command to remove the configuration, the specified
address/address range must be consistent with the one specified with the
dhcp server forbidden-ip
command. If you have configured to exclude an address range from dynamic assignment, you need to
specify the same address range in the
undo dhcp server forbidden-ip
command instead of specifying one
IP address.