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Configuring ARP restricted forwarding
ARP restricted forwarding controls the forwarding of ARP packets that are received on untrusted ports and
have passed ARP detection in the following cases:
If the packets are ARP requests, they are forwarded through the trusted ports.
If the packets are ARP responses, they are forwarded according to their destination MAC address. If
no match is found in the MAC address table, they are forwarded through the trusted ports.
Before performing the following configuration, make sure you have configured the
arp detection enable
command.
Follow these steps to enable ARP restricted forwarding:
To do…
Use the command…
Remarks
Enter system view
system-view
—
Enter VLAN view
vlan
vlan-id
—
Enable ARP restricted forwarding
arp restricted-forwarding enable
Required
Disabled by default.
Displaying and maintaining ARP detection
To do…
Use the command…
Remarks
Display the VLANs enabled
with ARP detection
display arp detection
[
|
{
begin
|
exclude
|
include
}
regular-expression
]
Available in any view
Display the ARP detection
statistics
display arp detection statistics
[
interface
interface-type interface-number
] [
|
{
begin
|
exclude
|
include
}
regular-expression
]
Available in any view
Clear the ARP detection
statistics
reset arp detection statistics
[
interface
interface-
type interface-number
]
Available in user view
ARP detection configuration example I
Network requirements
As shown in
, configure Switch A as a DHCP server and enable DHCP snooping on Switch B.
Configure Host A as a DHCP client. Configure Host B whose IP address is 10.1.1.6 and MAC address is
0001-0203-0607. Enable ARP detection for VLAN 10 to allow only packets from valid clients or hosts to
pass.