Displaying And Debugging Arp; Arp Configuration Examples - 3Com 5500-EI PWR Install Manual

The sending of gratuitous ARP packets is enabled as long as an S5500-EI switch operates. No
command is needed for enabling this function. That is, the device sends gratuitous ARP packets
whenever a VLAN interface is enabled (such as when a link is enabled or an IP address is
configured for the VLAN interface) or whenever the IP address of a VLAN interface is changed.
As for S5500-EI series Ethernet switches, before enabling the master switch of a VRRP backup
group to send gratuitous ARP packets periodically, you need to create the VRRP backup group
and perform corresponding configurations. Refer to the part discussing VRRP in this manual for
details.

Displaying and Debugging ARP

To do...
Display specific ARP mapping
table entries
Display the ARP mapping
entries related to a specified
string in a specified way
Display the number of the ARP
entries of a specified type
Display the statistics about the
untrusted ARP packets
dropped by the specified port
Display the setting of the ARP
aging timer
Clear specific ARP entries

ARP Configuration Examples

Network requirements
Disable ARP entry check on the switch.
Disable VLAN-interface 1 of the switch from sending gratuitous ARP packets periodically.
Set the aging time for dynamic ARP entries to 10 minutes.
Add a static ARP entry, with the IP address being 192.168.1.1, the MAC address being
000f-e201-0000, and the outbound port being Ethernet 1/0/10 of VLAN 1.
Configuration procedure
<Sysname> system-view
[Sysname] undo arp check enable
[Sysname] interface vlan 1
[Sysname-Vlan-interface1] undo gratuitous-arp period-resending enable
Use the command...
display arp [ static | dynamic | ip-address ]
display arp [ dynamic | static ] | { begin |
include | exclude } regular-expression
display arp count [ [ dynamic | static ] [ |
{ begin | include | exclude }
regular-expression ] | ip-address ]
display arp detection statistics interface
interface-type interface-number
display arp timer aging
reset arp [ dynamic | static | interface
interface-type interface-number ]
1-6
Remarks
Available in
any view
Available in
user view