Configuring ARP packet rate limit

About ARP packet rate limit

The ARP packet rate limit feature allows you to limit the rate of ARP packets delivered to the CPU. An ARP attack detection-enabled device will send all received ARP packets to the CPU for inspection. Processing excessive ARP packets will make the device malfunction or even crash. To solve this problem, configure ARP packet rate limit. When the receiving rate of ARP packets on the interface exceeds the rate limit, those packets are discarded.

You can enable sending notifications to the SNMP module or enable logging for ARP packet rate limit.

Restrictions and guidelines

As a best practice, configure this feature when ARP attack detection, ARP snooping, ARP fast-reply, or MFF is enabled, or when ARP flood attacks are detected.

If excessive notifications and log messages are sent for ARP packet rate limit, you can increase notification and log message sending interval.

If you enable notification sending and logging for ARP packet rate limit on a Layer 2 aggregate interface, the features apply to all aggregation member ports.

Procedure

  1. Enter system view.

    system-view

  2. (Optional.) Enable SNMP notifications for ARP packet rate limit.

    snmp-agent trap enable arp [ rate-limit ]

    By default, SNMP notifications for ARP packet rate limit are disabled.

  3. (Optional.) Enable logging for ARP packet rate limit.

    arp rate-limit log enable

    By default, logging for ARP packet rate limit is disabled.

  4. (Optional.) Set the notification and log message sending interval.

    arp rate-limit log interval interval

    By default, the device sends notifications and log messages every 60 seconds.

  5. Enter interface view.

    interface interface-type interface-number

    Supported interface types include Layer 2 Ethernet interface, Layer 3 Ethernet interface, Layer 3 aggregate interface, and Layer 2 aggregate interface.

  6. Enable ARP packet rate limit.

    arp rate-limit [ pps ]

    By default, ARP packet rate limit is enabled.