arp ip-conflict-detect enable

Function

The arp ip-conflict-detect enable command enables a device to log IP address conflicts.

The undo arp ip-conflict-detect enable command disables a device from logging IP address conflicts.

By default, IP address conflicts are not logged.

Format

arp ip-conflict-detect enable

undo arp ip-conflict-detect enable

Parameters

None

Views

System view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

When a device receives non-gratuitous ARP packets, it checks the IP addresses carried by the ARP packets. The device concludes that IP address conflicts exist on the network if any of the following conditions are met:

Local IP conflict occurs between a local device and another device. Specifically, a local device receives an ARP packet having the same source IP address but different MAC address with those of the interface receiving the packet.
Remote IP conflict occurs between devices and users attached to a local access device. Specifically, a local access device receives an ARP packet having the same source IP address but different MAC address with those of an ARP entry on the device.

When an IP address conflict occurs between network devices, it causes high CPU usage and route flapping. User services will be affected and even interrupted.

To better manage device addresses and rapidly locate a fault causing an IP address conflict, you can use the arp ip-conflict-detect enable command in the system view to enable a device to log IP address conflicts.

Precautions

After the arp ip-conflict-detect enable command is enabled, the device logs Remote IP conflicts.

Example

# Enable the device to log IP address conflicts.

<sysname> system-view

[sysname] arp ip-conflict-detect enable