21 Jun
2011
21 Jun
'11
7:45 p.m.
Hello,
On Tue, Jun 21, 2011 at 08:37:13PM +0100, Daniel Case wrote:
I think ports that aren't open usually show as
closed in nmap, it
doesn't bring them up, it says there are 996 closed ports which it
hasn't shown. I thought it might be a firewall on my end so I have
scanned a few more IP's and the port didn't come up on those... not
quite sure what's happening
I am fairly confident that when nmap says "filtered" it means it
didn't get any sort of response, but when it says "closed" it means
it got a connection reset (i.e. nothing listening on it but not
firewalled).
http://nmap.org/book/man.html
The output from Nmap is a list of scanned targets, with
supplemental information on each depending on the options
used. Key among that information is the “interesting ports
table”. That table lists the port number and protocol,
service name, and state. The state is either open, filtered,
closed, or unfiltered. Open means that an application on the
target machine is listening for connections/packets on that
port. Filtered means that a firewall, filter, or other
network obstacle is blocking the port so that Nmap cannot
tell whether it is open or closed. Closed ports have no
application listening on them, though they could open up at
any time.
Cheers,
Andy