Configuring ARP Cache Entry Timeout

You can specify how long an entry remains in the ARP cache using the arp timeout command. The default value is 21,600 seconds (6 hours). You can use the show config command to display the current value. If you specify a timeout of 0 seconds, entries are never cleared from the ARP cache.

Before you configure IP, you must create the lower-layer interfaces over which IP traffic flows. All IP configurations will be removed from the interface when you issue the no ip interface command in Interface Configuration mode.

To specify how long an entry remains in the ARP cache:

• Issue the arp timeout command in Interface Configuration mode.
  host1(config-if)#arp timeout 8000

  Note: You can issue this command only for Fast Ethernet interfaces, Gigabit Ethernet interfaces, 10-Gigabit Ethernet interfaces, and bridged Ethernet interfaces configured over ATM 1483.

  Use the no version to restore the default value.