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Does nmap work with ipv6? I don't even really know if ports are handled in the same way on ipv6 so I just wondered.

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Sorry, but -1 for apparent lack of any meaningful attempt to self-educate. – Chris S Mar 16 '11 at 12:30
+1 because we want this place to be a repository of questions, simple or not. Maybe someone else will google for "nmap ipv6" and find this and we can help them. – Mark Henderson Mar 17 '11 at 5:19
up vote 6 down vote accepted

Since 2002, Nmap has offered IPv6 support for its most popular features. In particular, ping scanning (TCP-only), connect scanning, and version detection all support IPv6. The command syntax is the same as usual except that you also add the -6 option. Of course, you must use IPv6 syntax if you specify an address rather than a hostname. An address might look like 3ffe:7501:4819:2000:210:f3ff:fe03:14d0, so hostnames are recommended. The output looks the same as usual, with the IPv6 address on the “interesting ports” line being the only IPv6 giveaway.


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One of the very interesting points talked about by one of the Cisco network leads at the Qualys stand at RSA was that the major difference is one of scale. I'll have to update this post when I get home and can source my notes, but he basically said the problem is that now the number of IP addresses he is responsible for is over 1 nonillion. That's a 1 with 30 zeros after it. Scanning a host for ports 1024-65535 can take some time, but assuming 1 minute per host, 1 nonillion hosts would take 1900 sextillion years.

So the real change in security scanning between IPv4 and IPv6 is around how you target hosts or subnets; no more blanket scanning of a range!

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