[Courses] [Security] safe use of nmap

[coldfire]

> Before I start nmapping my machines, I want to double check on
> something so I dont get my self in trouble.
> 
> There is one box I would like to scan, and thats my gateway machine. It
> has two nics, the public one and the private one.
> I would like to scan the public one, to see just whats listening.
> 
> Is it possible to scan a machine from the machine itself, or should you
> be on a second machine to scan the first?
> What I'm getting at is can I scan my public ip adress from the gateway
> machine itself?

you can port scan a particular machine from that machine itself .. but the
results can vary.  this, of course, depends on if the gateway machine is
configured as a firewall.  if not, i'm pretty sure you'll get an accurate
scan.

however, if you have a firewall configured on that machine, the results
from the scan could depend on rules which match 'localhost' for example.


coldie