H3C S5120-EI Series User Manual

1-6
z Determining whether its IP address is already used by another device.
z Informing other devices of its MAC address change so that they can update their ARP entries.
A device receiving a gratuitous ARP packet adds the information carried in the packet to its own
dynamic ARP table if it finds no corresponding ARP entry for the ARP packet in the cache.
Configuring Gratuitous ARP
Follow these steps to configure gratuitous ARP:
To do… Use the command… Remarks
Enter system view
system-view
—
Enable the device to send
gratuitous ARP packets when
receiving ARP requests from
another network segment
gratuitous-arp-sending
enable
Required
By default, a device cannot
send gratuitous ARP packets
when receiving ARP requests
from another network segment.
Enable the gratuitous ARP
packet learning function
gratuitous-arp-learning
enable
Optional
Enabled by default.
Displaying and Maintaining ARP
To do… Use the command… Remarks
Display ARP entries in the
ARP table
display arp [ [ all | dynamic | static ] [ slot
slot-number ] | vlan vlan-id | interface
interface-type interface-number ] [ [ |
{ begin | exclude | include }
regular-expression ] | count ]
Available in any view
Available in any view
Display the ARP entry for a
specified IP address
display arp ip-address [ slot slot-number ]
[ | { begin | exclude | include }
regular-expression ]
Available in any view
Display the aging time for
dynamic ARP entries
display arp timer aging
Available in any view
Clear ARP entries from the
ARP table
For distributed devices
reset arp { all | dynamic | static | slot
slot-number | interface interface-type
interface-number }
Available in user view

H3C S5120-EI Series Specifications

General

Brand	H3C
Model	S5120-EI Series
Category	Switch
Language	English