Re: Port Scanning Issues

For staters haveyou used Nmap also the host that is being scanned do you have a firewall on it, and if so is it setup to drop any icmp packets?

If you use nmap with a no ping scann and then look for tcp fiirst then udp you should get some results.

Nmap -P0 -sT
-sU for udp.
Sherwyn Williams
Technical Support
The Williams Solutions

-----Original Message-----
From: crumdub12@xxxxxxxxx

Date: 25 Jun 2007 21:59:58
Subject: Port Scanning Issues

A Chairde,

Havin, some issues with scanning stacks on my system.

1. Using Superscan4 , I scan stack UDP-TCP 1-65534 , Sometimes I

get no ports open , another time I get 49159 UDP Ports open, only get port report, no attempt made to open any ports ... , when get open ports , I always get 49159 UDP Ports ...... , use the scanner at 250msecs , takes around 16 hours to finish.

2. Using Languard, Nessus and Retina , get different scans from each tool, any ideas why, how do I find out real ports open.. differences can be 10,000 ports

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