Re: Port Scanning Issues

Hi Chaidre,

You could use the Connect scan option in nmap to get a more reliable scan. saying that i just realize that there are firewalls/load balancers that will respond with a SYN-ACK for every port, in that case i would say only when you send a data part of the connection after the ACK will you know if the port is really open. (people correct me if i am wrong). Hope it was of some help.

Regards
Vijay

crumdub12@xxxxxxxxx wrote:
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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