Network administrators may need a command or tool that will display all the live hosts in their network/subnet to keep track of all the activities and for that you can try using fping tool which works based on the ICMP echo request.
Fping rpm : http://packages.sw.be/fping
To install via yum on centos/fedora/rhel
# yum insall fping
After installing just execute the following command :
fping -g 192.168.1.0/24
fping -g 192.168.1.0 192.168.1.255
Fping Man Page : http://fping.sourceforge.net/man/