Microsoft DOS arp command

About arp

Displays, adds and removes arp information from network devices.

Short for Address Resolution Protocol, ARP is a protocol used with the IP protocol for mapping a 32-bit Internet Protocol address to a MAC address that is recognized in the local network specified in RFC 826. Once recognized, the server or networking device returns a response containing the required address.

• Additional information about the MS-DOS ARP command can be found on our MS-DOS ARP command page.
• See our Linux / Unix arp command page for additional information about this systems command.

Syntax ARP -s inet_addr eth_adr [if_addr]

ARP -d inet_addr [if_addr]
ARP -a [inet_addr] [-N if_addr]

-a	Displays current ARP entries by interrogating the current protocol data. If inet_addr is specified, the IP and Physical addresses for only the specified computer are displayed. If more than one network interface uses ARP, entries for each ARP table are displayed.
-g	Same as -a
inet_addr	Specifies an Internet address.
-N if addr	Displays the ARP entries for the network interface specified by if_addr.
-d	Deletes the host specified by inet_addr.
-s	Adds the host and associates the Internet address inet_addr with the Physical address eth_addr. The Physical address is given as 6 hexadecimal bytes seperated by hyphens. The entry is permanent.
eth_addr	Specifies a physical address
if_addr	If present, this specifies the Internet address of the interface whose address translation table should be modified. If not present, the first applicable interface will be used.

Examples

arp -a

Interface 220.0.0.80

Internet Address	Physical Address	Type
220.0.0.160	00-50-04-62-F7-23	static

The Physical Address or MAC address as shown above in the format aa-bb-cc-dd-ee-ff is the unique manufacturer identification number. This number should always be a unique address.

An example of how to change the above IP address 220.0.0.160 to 220.0.0.161 in this case would be:

arp -s 220.0.0.161 00-50-04-62-F7-23

If an IP address has already been assigned to the specific network adapter it is not possible to change that assigned IP address to a new address. In addition, networks italicizing DHCP, BOOTP or RARP will automatically assign the card an IP address, therefore, this command would not be utilized.