User Manual
UMN:CLI
V8102
419
snooping table and drop every ARP packet.
To specify the ARP inspection delay time, use the following command.
Command
Mode
Description
ip dhcp snooping arp-inspection
start
<1-2147483637>
Global
Configures the ARP inspection delay time. If reboot,
ARP inspection resumes after the time you configure.
1-2147483637: delay time (unit: second)
no ip dhcp snooping arp-
inspection start
Delete the configured ARP inspection delay time.
9.6.7.10
DHCP Snooping with Option82
In case of L2 environment, when forwarding DHCP messages to a DHCP server, a DHCP
switch can insert or remove DHCP option82 data on the DHCP messages from the clients.
In case of a switch is enabled with DHCP snooping, it floods DHCP packets with DHCP
option82 field when the DHCP option82 is enabled. This allows an enhanced security and
efficient IP assignment in the Layer 2 environment with a DHCP option82 field.
If DHCP snooping is enabled in the system of V8102, DHCP packets includes DHCP op-
tion82 field by default.
To enable/disable the switch which is enabled by DHCP snooping to insert or remove
DHCP option82 field, use the following command.
Command
Mode
Description
ip dhcp snooping information
option
Global
Enables the switch to insert DHCP option 82 field in
forwarded DHCP packets to the DHCP server.
no ip dhcp snooping infor-
mation option
Disables the switch not to insert DHCP option 82 field
in forwarded DHCP packets to the DHCP server
9.6.7.11
DHCP Snooping Option
DHCP snooping switch may receive DHCP messages (Discover/Request) with various
different options from clients, which cause DHCP server hard to manage
client’s infor-
mation in the perspective of data consistency. That
’s why this function is necessary.
The switch operating DHCP snooping can modify or attach an option field of the DHCP
messages (Discover/Request) with a defined snooping option and can forward them to
DHCP server. The snooping option can be applied on a port basis or on entire ports. Be-
fore using this function, a global DHCP option format should be created. For details of
setting the DHCP option format, refer to the
To set a DHCP snooping option for a specific port, use the following command.
Command
Mode
Description
ip dhcp snooping opt-code
<1-254>
format NAME
Interface
[XE/GE/GPON/CG]
Specifies a snooping option format on a port.
opt-code: DHCP option code
NAME: DHCP option format name
ip dhcp snooping opt-code
<1-254>
policy
{
keep
|
re-
Configures a policy against DHCP option
belonging to a DHCP message (default:
i