Flushing the ARP Cache

This article explains how to flush the ARP cache of a firewall

Resolution for SonicOS 7.X

This release includes significant user interface changes and many new features that are different from the SonicOS 6.5 and earlier firmware. The below resolution is for customers using SonicOS 7.X firmware.

 
It is sometimes necessary to flush the ARP cache if the IP address has changed for a device on the network.  Since the IP address is linked to a physical address,
the IP address can change but still be associated with the physical address in the ARP cache.

Flushing the ARP Cache allows new information to be gathered and stored in the ARP Cache.

• Navigate to Network | System | ARP tab.
• The ARP cache will be displayed on screen.
• Select Flush ARP Cache to clear the ARP table.
  
  
  
  
• To configure a specific length of time for the entries to time out, navigate to ARP Settings at top and enter value in minutes under ARP Cache entry timeout (minutes) field.
  
  
  
  
  

Resolution for SonicOS 6.5

This release includes significant user interface changes and many new features that are different from the SonicOS 6.2 and earlier firmware. The below resolution is for customers using SonicOS 6.5 firmware.

It is sometimes necessary to flush the ARP cache if the IP address has changed for a device on the network.  Since the IP address is linked to a physical address,
the IP address can change but still be associated with the physical address in the ARP cache.

Flushing the ARP Cache allows new information to be gathered and stored in the ARP Cache.

• Navigate to Manage | Network | ARP tab.
  
• Select Flush ARP Cache to clear the ARP table.

• To configure a specific length of time for the entries to time out, enter a value in minutes in the ARP Cache entry time out (minutes) field.