H3C S3100 8C SI User Manual

Operation Manual – ARP
H3C S3100 Series Ethernet Switches Chapter 1 ARP Configuration
1-7
1.1.8 Introduction to Gratuitous ARP
The following are the characteristics of gratuitous ARP packets:
z Both source and destination IP addresses carried in a gratuitous ARP packet are
the local addresses, and the source MAC address carried in it is the local MAC
addresses.
z If a device finds that the IP addresses carried in a received gratuitous packet
conflict with those of its own, it returns an ARP response to the sending device to
notify of the IP address conflict.
By sending gratuitous ARP packets, a network device can:
z Determine whether or not IP address conflicts exist between it and other network
devices.
z Trigger other network devices to update its hardware address stored in their
caches.
The gratuitous ARP packet learning function:
When the gratuitous ARP packet learning function is enabled on a switch and the
switch receives a gratuitous ARP packet, the switch can add the information carried in
the packet to its own dynamic ARP mapping table if it finds no corresponding ARP entry
for the ARP packet in the cache.
1.2 ARP Configuration
1.2.1 Configuring ARP Basic Functions
Table 1-4 Configure ARP basic functions
Operation Command Remarks
Enter system view
system-view
—
Add a static ARP entry
arp static ip-address
mac-address [ vlan-id
interface-type
interface-number ]
Optional
By default, the ARP
mapping table is
empty, and the
address mapping
entries are created
dynamically by ARP.
Configure the ARP aging
timer
arp timer aging
aging-time
Optional
By default, the ARP
aging timer is set to 20
minutes.

H3C S3100 8C SI Specifications

General

Brand	H3C
Model	S3100 8C SI
Category	Switch
Language	English