Extract uniq IPs from file and perform whois look up

ipchecker.sh

#!/bin/bash

# Check if an input file is provided
if [ $# -ne 1 ]; then
    echo "Usage: $0 <input_file>"
    exit 1
fi

input_file="$1"

# Extract unique IP addresses from the file
unique_ips=$(grep -oE "\b([0-9]{1,3}\.){3}[0-9]{1,3}\b" "$input_file" | sort -u)

# Perform nslookup for each IP
for ip in $unique_ips; do
    #echo "IP: $ip"
    whois -h whois.cymru.com " -v $ip"
    echo
done