Search alive hosts.

Search alive hosts. - use fping : fping -g -a ip range

   option -a : Forces the tool to show only alive hosts.
              -g : Tool that we are using a range and note a single ip.
  
                ex). fping -g -a 192.168.0.1/24
                      view other options : http://fping.sourceforge.net/man

 - use nmap : nmap -iL live.txt -sP ip range

    option -iL : Tool to read the IP addresses to use in the scan from live.txt
              -sP : ping sweep scan.

               ex). nmap -sP 192.168.0.1/24
                     view other options : http://nmap.org/book/man-briefoptions.html