Generate random IP addresses

nmap -n -iR 0 -sL | cut -d" " -f 2
It never ends
Sample Output 
(... ad infinitum ...)

By: kovan
2009-08-12 16:49:55

What Others Think

The command is correct, and works as described. However, I can't see this used for anything other than malicious purposes. Maybe stated more mildly: I see no practical or business application whatsoever-- only suitable to be fed back to nmap for a spoofing list. Why else would you want this.
linuxrawkstar · 624 weeks and 4 days ago
It does not generate random IP adresses, it scans them! And this could be, depending on your country, illegal!
peshay · 624 weeks and 3 days ago
@peshay: the command does exactly what is described. It does not send a single packet through the net. This is from the man page of nmap, which you should have read before commenting that. "-sL (List Scan) The list scan is a degenerate form of host discovery that simply lists each host of the network(s) specified, without sending any packets to the target hosts. (...) Since the idea is to simply print a list of target hosts, options for higher level functionality such as port scanning, OS detection, or ping scanning cannot be combined with this.
kovan · 624 weeks and 2 days ago
@linuxrawkstar Oh boo hoo, I don't get why generating a large list of IPs is bad, in my free time one of the things I like to do is penetration testing (without prior permission, I only email the admin if I find a way in) which i dont see as "malicious" and how about real pen testing? A comment for the command is that with nmap 6.25 on Gentoo I have to change the cut parameters to "cut =d" " -f 5" but this may be different on other machines/operating systems. Also to save them its better to: nmap -n -iR -sL | cut -d" " -f 5 >> /path/to/file.txt I often run random scans of 10K-100K IPs with nmap and then pen test the interesting ones.
Asphyxiated · 441 weeks and 5 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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