ARP

The ARP resolves IPv4 network layer addresses to link layer MAC addresses. addresses. This mapping is essential for communication within the Internet Protocol suite. ARP was standardized in 1982 by RFC 826 (STD 37).

Note

In Internet Protocol version 6 (IPv6) networks, address resolution is performed by the Neighbor Discovery Protocol (NDP).

Use the following commands to configure or view ARP table entries.

Configuration

set protocols static arp interface <interface> address <host> mac <mac>

Configure a static ARP entry on the specified interface.

This creates a permanent mapping between an IP address and a MAC address on the specified interface.

Example:

set protocols static arp interface eth0 address 192.0.2.1 mac 01:23:45:67:89:01

Operation

show protocols static arp

Show all ARP table entries across all interfaces.

vyos@vyos:~$ show protocols static arp
Address                  HWtype  HWaddress           Flags Mask     Iface
10.1.1.1                 ether   00:53:00:de:23:2e   C              eth1
10.1.1.100               ether   00:53:00:de:23:aa   CM             eth1

show protocols static arp interface <interface>

Show all ARP table entries for the specific interface.

Example for eth1:

vyos@vyos:~$ show protocols static arp interface eth1
Address                  HWtype  HWaddress           Flags Mask     Iface
10.1.1.1                 ether   00:53:00:de:23:2e   C              eth1
10.1.1.100               ether   00:53:00:de:23:aa   CM             eth1