Bash: Script to find active computers in a subnet using ping
The following is a simple bash script that will scan each ip address in a give subnet and report if they are alive (or accepting ping requests). The code creates processes for each ping so that it completes quickly rather than scanning each ip address sequentially.
Create a text file called “pinger.sh” and paste the following into it:
#!/bin/sh
: ${1?"Usage: $0 ip subnet to scan. eg '192.168.1.'"}
subnet=$1
for addr in `seq 0 1 255 `; do
# ( echo $subnet$addr)
( ping -c 3 -t 5 $subnet$addr > /dev/null && echo $subnet$addr is Alive ) &
done
Save and close, then it can be called from the command line like so:
sh pinger.sh 192.168.1.
This will scan from 192.168.1.0 to 192.168.1.255 and will return something like the following:
192.168.1.1 is Alive 192.168.1.105 is Alive 192.168.1.112 is Alive 192.168.1.149 is Alive