3Com Switch 7750 Configuration Guide Guide

552 CHAPTER 52: ARP CONFIGURATION
Configuring Maximum
Number of ARP Entries
to Be Learnt
Use the following commands to configure the maximum number of ARP entries
that can be learnt.
Configuring the ARP
Aging Timer for
Dynamic ARP Entries
The ARP aging timer applies to all dynamic ARP mapping entries.
Enabling the ARP Entry
Checking Function
When multiple hosts share one multicast MAC address, you can specify whether
or not to create multicast MAC address ARP entries for MAC addresses learned by
performing the operations listed in
Table 423.
Configuring Sending of
Gratuitous ARP Packets
On the Switch 7750 Family, the sending of gratuitous ARP packets is always
enabled; no additional configuration is required. That is, The device sends
gratuitous ARP packets whenever a VLAN interface becomes 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.
Configuring the
Gratuitous ARP packet
Learning Function
Table 424 lists the operations to configure the gratuitous ARP packet learning
function.
Tabl e 421 Configure the maximum number of ARP entries to be learnt
Operation Command Description
Enter system view system-view -
Configure the limit number of
ARP entries
arp max-entry number
Optional
8192 by default.
Enter corresponding interface
view
interface interface-type
interface-number
-
Configure the maximum
number of dynamic ARP
entries that can be learnt by
an interface
arp max-dynamic-entry
number
Optional
2048 by default
Tabl e 422 Configure the ARP aging timer for dynamic ARP entries
Operation Command Description
Enter system view system-view -
Configure the ARP aging
timer
arp timer aging aging-time
Optional
By default, the ARP aging
timer is set to 20 minutes.
Tabl e 423 Enable the ARP entry checking function
Operation Command Description
Enter system view system-view -
Enable the ARP entry checking
function (that is, disable the
switch from creating multicast
MAC address ARP entries for
MAC addresses learned)
arp check enable
Optional
By default, the ARP entry
checking function is enabled.
Tabl e 424 Configure the gratuitous ARP packet learning function
Operation Command Description
Enter system view system-view -