Scan Random Targets The -iR parameter can be used to select random internet hosts to scan. Nmap will randomly generate the specified number of targets and attempt to scan them. Usage syntax: nmap -iR [number of targets] # nmap -iR 3 Starting Nmap 5.00 ( http://nmap.org ) at 2009-08-07 23:40 CDT ... Nmap done: 3 IP addresses (2 hosts up) scanned in 36.91 seconds Scanning three randomly generated IP addresses note For privacy reasons we do not display the results of the above scan in this book. Executing nmap -iR 3 instructs Nmap to randomly generate 3 IP addresses to scan. There aren’t many good reasons to ever do a random scan unless you are working on a research project (or just really bored). Additionally, if you do a lot of aggressive random scanning you could end up getting in trouble with your internet service provider.