Configuring Address Resolution Protocol (Arp); Clearing Arp Cache Entries; Configuring Arp Refresh Interval - HP procurve 8100fl series Management And Configuration Manual

IP Routing Configuration

Configuring Address Resolution Protocol (ARP)

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11-8
Configuring Address Resolution
Protocol (ARP)
The Address Resolution Protocol (ARP) is used to associate IP addresses with
media or MAC addresses. Taking an IP address as input, ARP determines the
associated MAC address. Once a media or MAC address is determined, the IP
address/media address association is stored in an ARP cache for rapid
retrieval. Then the IP datagram is encapsulated in a link-layer frame and sent
over the network.

Clearing ARP Cache Entries

To remove the ARP entry for the host 10.8.1.2 from the ARP table:.
ProCurve#clear arp 10.8.1.2
To clear the entire ARP table.
ProCurve#clear arp-cache
The clear arp command is only used to clear an individual arp entry, while the
clear arp cache command clears all arp entries from the entire arp table.
If the Startup configuration file contains arp add commands, the Management
Module re-adds the ARP entries even if you have cleared them using the clear
arp commands. To permanently remove an ARP entry, use the no command to
remove the entry.

Configuring ARP Refresh Interval

The arp refresh command causes an ARP packet to be issued periodically for
stations currently known in the router's ARP cache. This packet refreshes the
entry to prevent timeout of the ARP entry. It also helps detect MAC station
movement between different ports of a VLAN.
In the case of VLANs, implementing this command is highly recommended as
it helps detect MAC movement changes due to either physical station moves
or changes in network topology regardless of whether or not ARP packets are
being re-issued by the moving station.