H3C S6812 Series Command Reference Manual page 765

Syntax
dhcp snooping enable
undo dhcp snooping enable
Default
DHCP snooping is disabled.
Views
System view
Predefined user roles
network-admin
Usage guidelines
Use the DHCP snooping feature together with the trusted port configuration. Trusted ports forward
responses from DHCP servers and untrusted ports discard responses from DHCP servers. This
mechanism ensures that DHCP clients obtain IP addresses from authorized DHCP servers.
When DHCP snooping is disabled, all ports on the device forward responses from DHCP servers.
Examples
# Enable DHCP snooping.
<Sysname> system-view
[Sysname] dhcp snooping enable
dhcp snooping information circuit-id
Use dhcp snooping information circuit-id to configure the padding mode and padding format for
the Circuit ID sub-option.
Use undo dhcp snooping information circuit-id to restore the default.
Syntax
dhcp snooping information circuit-id { [ vlan vlan-id ] string circuit-id | { normal | verbose
[ node-identifier { mac | sysname | user-defined node-identifier } ] } [ format { ascii | hex } ] }
undo dhcp snooping information circuit-id [ vlan vlan-id ]
Default
The padding mode is normal and the padding format is hex.
Views
Layer 2 Ethernet interface view
Layer 2 aggregate interface view
Predefined user roles
network-admin
Parameters
vlan vlan-id: Pads the Circuit ID sub-option for packets received from the specified VLAN. If you do
not specify a VLAN, the device pads the Circuit ID sub-option for packets received from the default
VLAN.
string circuit-id: Specifies the string mode, in which the padding content for the Circuit ID sub-option
is a case-sensitive string of 3 to 63 characters.
82