Reference Guide

IPv4 Routing | 469
ARP
Dell Networking OS uses two forms of address resolution: ARP and Proxy ARP.
Address Resolution Protocol (ARP) runs over Ethernet and enables endstations to learn the MAC
addresses of neighbors on an IP network. Over time, Dell Networking OS creates a forwarding table
mapping the MAC addresses to their corresponding IP address. This table is called the ARP Cache and
dynamically learned addresses are removed after a defined period of time.
For more information on ARP, see RFC 826,
An Ethernet Address Resolution Protocol.
In Dell Networking OS, Proxy ARP enables hosts with knowledge of the network to accept and forward
packets from hosts that contain no knowledge of the network. Proxy ARP makes it possible for hosts to be
ignorant of the network, including subnetting.
For more information on Proxy ARP, refer to RFC 925,
Multi-LAN Address Resolution, and RFC 1027, Using
ARP to Implement Transparent Subnet Gateways.
Configuration Task List for ARP
The following list includes configuration tasks for ARP:
• Configuring static ARP entries (optional)
• Enabling Proxy ARP (optional)
• Clearing ARP cache (optional)
• ARP Learning via Gratuitous ARP
• ARP Learning via ARP Request
• Configuring ARP Retries
For a complete listing of all ARP-related commands, refer to the
Dell Networking OS Command Line
Reference.
Configuring static ARP entries
ARP dynamically maps the MAC and IP addresses, and while most network host support dynamic
mapping, you can configure an ARP entry (called a static ARP) for the ARP cache.
To configure a static ARP entry, use the following command in the CONFIGURATION mode: