3Com 7757 Configuration Manual page 577

Configuring the Aging
Time for Dynamic ARP
Entries
Configuring ARP Entry
Checking
Enabling ARP
Forwarding in the
Protocol-Based VLAN
c
Table 450 Configure the maximum number of ARP entries that can be learnt on a port
Operation
Enter port view
Configure the maximum
number of dynamic ARP
entries that can be learnt by
the port
Table 451 Configure the aging time for dynamic ARP entries
Operation
Enter system view
Configure the aging time for
dynamic ARP entries
Table 452 Enable ARP entry checking
Operation
Enter system view
Enable ARP entry checking to
disable the switch from learning
ARP entries with multicast MAC
addresses
The system allows for classifying VLANs based on protocols, and such VLANs are
called protocol-based VLANs. For details, refer to "Protocol-Based VLAN" on page
91. After you enable ARP in a protocol-based VLAN, the switch can forward ARP
packets through the receiving interfaces based on the operating mechanism.
However, this may affect other devices to learn ARP entries in practice.
To prevent the switch from forwarding ARP requests out the receiving interfaces,
you need to disable ARP and disable ARP forwarding in the protocol-based VLAN.
For commands about disabling ARP in a protocol-based VLAN, refer to
"Protocol-Based VLAN" on page 91.
Table 453 Enable ARP forwarding in the protocol-based VLANs
Operation
Enter system view
Enable ARP forwarding in the
protocol-based VLAN(s)
CAUTION: Since the close relation between IP and ARP, disabling ARP or ARP
forwarding in a protocol-based VLAN may cause incorrect IP-to-MAC resolutions.
Command
interface interface-type
interface-number
arp max-dynamic-entry
number
Command
system-view
arp timer aging aging-time
Command
system-view
arp check enable
Command
system-view
arp relay enable
Configuring ARP
Description
-
Optional
It is 2048 by default.
Description
-
Optional
By default, this time is 20
minutes.
Description
-
Optional
By default, the function is
enabled and no multicast MAC
address ARP entry will be learnt.
Description
-
Optional
By default, the feature is
enabled.
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