The Address Resolution Protocol (ARP) is an essential protocol used in computer networks. It allows computers to map IP addresses to physical addresses like Ethernet MAC addresses, allowing them to communicate over the network.
The arp command is a Microsoft Windows-based command line utility that can be used to view and modify the ARP cache. The arp -a command displays all current entries in the ARP cache table, including both static and dynamic entries. It can also be used to add or delete entries from the ARP table. This is useful for troubleshooting network issues, as it can help identify incorrect or missing entries in the ARP table.
ARP -s inet_addr eth_addr [if_addr]
ARP -d inet_addr [if_addr]
ARP -a [inet_addr] [-N if_addr] [-v]
arp -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.
arp -g Same as -a.
arp -v Displays current ARP entries in verbose mode. All invalid
entries and entries on the loop-back interface will be shown.
inet_addr Specifies an internet address.
arp -N if_addr Displays the ARP entries for the network interface specified
by if_addr.
arp -d Deletes the host specified by inet_addr. inet_addr may be
wildcarded with * to delete all hosts.
arp -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 separated 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.
Example:
arp -s 157.55.85.212 00-aa-00-62-c6-09 …. Adds a static entry.
arp -a …. Displays the arp table.
