What is Arp Command Line Tool

When you are troubleshooting, there are several tools that will allow you to quickly determine whether or not the network is the source of a problem. In this tutorial, we'll look at the Arp command line troubleshooting tool.

Numerous command line tools exist for managing Microsoft networks. We will focus on usage details of the Arp command line tool included with Windows OS. We will look at Arp command line and its syntax, as well as outline the situations where each command is most useful.

The arp command is derived from Address Resolution Protocol (ARP), which is a required TCP/IP standard. Every piece of hardware connected to a network has a unique 48-bit Media Access Control (MAC) address, which is normally expressed in hexadecimal. ARP is used to associate a network interface's MAC address, such as 00-60-87-40-1B-BD, to its IP address, such as 168.0.0.10.

The Address Resolution Protocol (ARP), will be use when one system needs to contact another system on its local subnet, it broadcasts an ARP request on the local subnet, the ARP broadcast request made for the MAC address of the system with given ip address. Once the MAC address for that IP address is discovered, it is stored in the system's ARP cache. By caching IP address–to–MAC address associations, the system will not have to broadcast an ARP request the next time a computer needs to send a packet to the same system on its local subnet.

The arp command can be handy for troubleshooting when one system cannot contact another system on the same subnet.

When two systems on the same subnet were accidentally assigned the same IP address, you would run into an improper ARP cache entry. When this happens, a computer could have the wrong MAC address cached for a particular IP address. This is where the arp command is useful.

What is Arp Command Line Tool X3NvBLn

Here are some examples of using arp command for troubleshooting.

  • Display the entire ARP cache on a computer with a single NIC: arp -a

  • Delete an invalid entry in the ARP cache: arp -d 168.60.5.20

  • Add a static entry to the ARP cache: arp -s 168.88.5.205   00-aa-73-51-b8-4e