arp:tldr:09258

arp: Show the current ARP table.

$ arp -a

try on your machine

The command "arp -a" is used to display the ARP (Address Resolution Protocol) cache on a computer.

When devices communicate on a network, they use IP (Internet Protocol) addresses to identify each other. However, actual communication occurs at the link layer using MAC (Media Access Control) addresses. ARP is responsible for resolving IP addresses to MAC addresses.

The "-a" option with the "arp" command stands for "all" and is used to display the full ARP cache. The ARP cache is a table that contains the IP-MAC address mappings for devices on the local network.

When you execute the command "arp -a," it will show a list of IP addresses and their corresponding MAC addresses for the devices that the computer has communicated with recently. This information is cached to speed up future communication by avoiding the need to perform ARP lookups for frequently accessed devices.

This explanation was created by an AI. In most cases those are correct. But please always be careful and never run a command you are not sure if it is safe.

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