3com 8807 User Guide

Page of 883
720
C
HAPTER
 60: NDP C
ONFIGURATION
On the management device, NDP must be enabled in the system and on the 
ports.
On member devices and candidate devices, the NPD feature must also be 
enabled in the system and on the corresponding ports. The aging timer for the 
NDP information sent from the management device is used during NDP 
operation.
Enabling NDP in the 
System
To collect the NDP information sent by the neighbor device, you must enable NDP 
on the switch. With NDP enabled in the system, the switch periodically collects 
NDP information, which you can query by using the display ndp command. With 
NDP disabled in the system, the switch clears all NDP neighbor information stored 
on it but will still forwards NDP packets.
When you try to enable NDP on all ports, NDP is enabled only on the common 
Ethernet ports and Gigabit Ethernet ports that support NDP interface modules.
Configuring NDP on a 
Port
You can control the collection of neighbor device information for the specified 
port by enabling/disabling NDP on the port. With NDP enabled on the port and in 
the system, the system periodically collects the NDP neighbor information about 
the adjacent node of the port. With NDP disabled on the port, the system cannot 
collect NDP information through the port.
Configuring the Aging 
Timer for NDP 
Information
Upon receipt of NDP packets, from the aging timer information carried in the 
packets, the switch can learn about the aging timer for the NDP information of 
the neighbor device that sent the packets and discards the NDP information of the 
neighbor device once the aging timer is exceeded. This configuration allows you to 
set the aging timer for the NDP information of the current device on the neighbor 
device.
Table 664   Enable NDP in the system
Operation 
Command 
Description 
Enter system view 
system-view 
Enable NDP in the system 
ndp enable [ interface 
port-list | all ] 
By default, NDP is disabled in 
the system.
Table 665   Enable NDP on a port
Operation 
Command 
Description 
Enter system view 
system-view 
Enter Ethernet port view 
interface interface-type 
interface-number
 
Currently, only common 
Ethernet interface modules 
and Gigabit Ethernet interface 
modules support NDP. 
Enable NDP on the port 
ndp enable 
By default, NDP is disabled on 
a port.
Table 666   Configure the aging timer for NDP information
Operation 
Command 
Description 
Enter system view 
system-view