When ping fails: Use ARP

If traditional ICMP-based pings are no longer reliable unless you know in advance that there is no firewall blocking ICMP echo requests, what other options exist? One option is an Address Resolution Protocol (ARP) based ping using the arping utility.

To know why ARP pings are virtually guaranteed to work while ICMP pings may not, one should understand the importance of ARP in networking. ARP is used by hosts on a network to resolve IP addresses into Media Access Control (MAC) addresses, which can be interpreted as a network interface's unique serial number. Hosts on an Ethernet network use MAC addresses rather than IP addresses to communicate.