Open ports on FC2

[Jorge Fábregas]

On Saturday 24 July 2004 4:16 pm, Chris Hewitt wrote:
> ..but that told John he had ports 21 and 23 with servers on. I'm a bit
> suspicious.

Hi,

This is John's post:

> Tell inquirers that ports 21 and 23 exist but are 
> closed to connections

It didn't say that those ports were open. It probably means that he has some 
ACL (access control list) on the server, thru inetd, xinetd or the daemons 
themselves...and when someone attempts these ports on his machine you're just 
denied access (but that's the problem: you know they are there!).  That's the 
main difference between REJECT and DROP when you use  iptables. With DROP the 
port scanner will not receive a response back. With REJECT you'll get a 
response back.  Youl should avoid REJECT...and always use DROP (it's way 
better..as you're completely STEALTH).  The only reason for using REJECT 
(that I can think of) is for trouble-shooting purposes.