User Manual

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[Example]
Disables MAC address verification setting.
SWP2(config)#ip dhcp snooping verify mac-address disable
6.5.5 Enable/disable Option 82 setting
[Syntax]
ip dhcp snooping information option switch
no ip dhcp snooping information option
[Parameter]
switch : Option 82 setting
Setting value Description
enable Enable setting for Option 82
disable Disable setting for Option 82
[Initial value]
ip dhcp snooping information option enable
[Input mode]
global configuration mode
[Description]
Enables/disables the settings for adding, inspecting and deleting Option 82 information in DHCP packets.
If this command is executed with the "no" syntax, the setting returns to the default.
When Option 82 is enabled, the Option 82 information is added to DHCP packets received from the DHCP client on the
untrusted port,
and the return packets are forwarded to the DHCP client from the DHCP server with the Option 82 information deleted.
The Option 82 information is as follows.
Remote-ID
The MAC address of this device is added by default.
You can use the ip dhcp snooping information option format remote-id command to add a desired text string
(single-byte alphanumeric characters and single-byte symbols) to the Remote-ID.
Circuit-ID
The VLAN ID that received the DHCP packet from the DHCP client as well as the interface number are added by
default.
Use the ip dhcp snooping vlan vlan-id information option format-type circuit-id command to change the Circuit-ID
information to the VLAN ID that received the DHCP packet from the DHCP client as well as the port number.
Subscriber-ID
Not added by default.
You can use the ip dhcp snooping subscriber-id command to set the desired text string for the Subscriber-ID of the
applicable port.
When a DHCP packet to which Option 82 information has already been added is received, that DHCP packet is discarded.
You can use the ip dhcp snooping information option allow-untrusted command to permit forwarding of DHCP packets that
include Option 82 information at the untrusted port.
[Example]
This disables Option 82 settings.
SWP2(config)#ip dhcp snooping information option disable
6.5.6 Settings for permitting receipt of packets on an untrusted port, including Option 82 information
[Syntax]
ip dhcp snooping information option allow-untrusted
no ip dhcp snooping information option allow-untrusted
220 | Command Reference |
Layer 2 functions