Nmap wont allow you to scan on own IP unless you are scanning from the outside that is the internet.
Which also requires a fair amount of understanding of ports & various options present in nmap.
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The protection of a machine is a process & not a given -Duane Arnold.
www.Oobertech.net
Look ma my blog http://techhub.blogspot.com/
Hmm ... I was able to use nmap to scan my local PC quite simply -
Quote:
$ nmap 127.0.0.1
Starting nmap 3.81 ( http://www.insecure.org/nmap/ ) at 2005-06-14 16:24 IST
Interesting ports on archlinux.sify (127.0.0.1):
(The 1662 ports scanned but not shown below are in state: closed)
PORT STATE SERVICE
6000/tcp open X11
Nmap finished: 1 IP address (1 host up) scanned in 5.901 seconds
But I guess I am missing something here, as I do not know much about networking.
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Hardware - Celeron 266 MHz, 128MB RAM, Intel i740 8MB RAM
Software - Slackware Linux 10.1; Archlinux 0.7; Windows 98 SE
Humanware - GS/CS C++ L+++ w b+++ DI+ D+ e
Retina would probably be an overkill for this. There are online vulnerability scanners out there on the web like the one digen suggested. Here are a few others.