fping is a ping(1) like program which uses the Internet Control Message
Protocol (ICMP) echo request to determine if a host is up. fping is different
from ping in that you can specify any number of hosts on the command line, or
specify a file containing the lists of hosts to ping. Instead of trying one
host until it timeouts or replies, fping will send out a ping packet and move
on to the next host in a round-robin fashion. If a host replies, it is noted
and removed from the list of hosts to check. If a host does not respond within
a certain time limit and/or retry limit it will be considered unreachable.