Script to find online hosts on the network then check for ports / services running on online hosts

nmap-port-scan.sh

#!/bin/bash
echo "script starting..."

# installs nmap
apt update
apt install nmap -y
echo "nmap has been installed"

# finds hosts that are online on the network and outputs it to a online-hosts.txt file in the current dir
nmap -sn 192.168.1.0/24 -oG - | awk '/Up$/{print $2}' > online-hosts.txt

# runs nmap again to find open ports
nmap -iL online-hosts.txt -p- -oN port-scan-results.txt

echo "script complete"