Configuring an ARP Miss Message Rate Limit

If a device generates a large number of ARP Miss messages in a specified period of time, the device will not process the ARP Miss messages exceeding a configured threshold.

Background Information

After the ARP Miss message rate limit is configured, the device counts the number of received ARP Miss messages. If the number of ARP Miss messages received in a specified period exceeds a specified limit, the device does not process additional ARP Miss messages.

If a large number of VLANs are configured on an interface, ARP request packets that are triggered by ARP Miss messages need to be copied and sent on all these VLANs, causing the software to be overloaded and not to be able to send ARP request packets to terminals in time. To resolve this problem, you can configure a penalty interval to suppress dynamic ARP fake entry aging. When ARP Miss messages are triggered again after ARP learning fails, the system accumulatively increases the aging time of fake ARP entries by the configured penalty interval to dynamically prolong the life cycle of ARP fake entries, reducing the software workload of sending ARP request packets.

Procedure

Configure ARP Miss message rate limit based on source IP addresses.
1. Run system-view
  The system view is displayed.
2. Run arp-miss speed-limit source-ip maximum maximum [ slot slot-id ]
  ARP Miss message rate limit based on source IP addresses is configured.
3. Run commit
  The configuration is committed.
(Optional) Setting the aging expiry time of a fake dynamic ARP Entries.
1. Run system-view
  The system view is displayed.
2. Run interface interface-type interface-number
  The interface view is displayed.
3. Run arp-fake expire-time expire-time
  The aging expiry time of a fake dynamic ARP entries is set.
4. Run commit
  The configuration is committed.
(Optional) Configure a penalty interval to suppress dynamic ARP fake entry aging.
1. Run system-view
  The system view is displayed.
2. Run interface interface-type interface-number
  The interface view is displayed.
3. Run arp-fake penalty-time penalty-time
  A penalty interval is configured to suppress dynamic ARP fake entry aging.
  
  If the aging time of dynamic ARP fake entries is set using the arp-fake expire-time command, the penalty interval configuration does not take effect.
4. Run commit
  The configuration is committed.