Allied Telesis IE340 Series User Manual

C613-50631-01 Rev A Command Reference for IE340 Series 2553
AlliedWare Plus™ Operating System - Version 5.5.3-0.x
DHCP SNOOPING COMMANDS
ARP
SECURITY DROP LINK-LOCAL-ARPS
arp security drop link-local-arps
Overview Use this command to enable ARP security on a per-port basis. This means that IPv4
link-local ARPs will be dropped without causing an ARP security violation when
received.
Use the no variant of this command to return to the default setting of disabled.
Syntax
arp security drop link-local-arps
no arp security drop link-local-arps
Default Disabled by default.
Mode Interface Configuration
Usage notes Hosts that implement RFC 3927 may automatically assign themselves link-local
IPv4 addresses in the subnet 169.254.0.0/16, if they are configured to learn their IP
addresses via DHCP but are unable to contact a DHCP server. This is common
behavior for all versions of Microsoft Windows since Windows XP. In an attempt to
avoid IP address collision with other devices on the local network, the host will
broadcast ARP probes for its randomly selected link-local IP address.
By default, ARP security will treat these ARP probes as violations and carry out the
configured violation action on the port they are received on. If the violation action
is configured as link-down, this will result in the host being disconnected from the
network, which will interrupt any DHCP IP address discovery that was in progress.
Use this command to configure ARP Security to drop these ARP probes, and any
other ARPs that contain link-local IP addresses, without raising a violation on the
affected port. The count of ARPs dropped in this manner can be seen in the output
of show arp security statistics detail.
Example To configure ARP security to drop IPv4 link local ARPs on port1.0.1 to port1.0.4, use
the commands:
awplus# configure terminal
awplus(config)# interface port1.0.1-port1.0.4
awplus(config-if)# arp security drop link-local-arps
Related
commands
arp security
arp security violation
show arp security statistics
Command
changes
Version 5.4.9-1.1: command added.

Allied Telesis IE340 Series Specifications

General

Brand	Allied Telesis
Model	IE340 Series
Category	Switch
Language	English