LinuxQuestions.org
Download your favorite Linux distribution at LQ ISO.
Home Forums Tutorials Articles Register
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Networking
User Name
Password
Linux - Networking This forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.

Notices


Reply
  Search this Thread
Old 03-30-2004, 08:17 PM   #1
dareino
Member
 
Registered: Mar 2004
Location: S.F.,Ca
Distribution: FC4
Posts: 82

Rep: Reputation: 15
Ports listening?


When I open/forward a port and I start the Application, shouldnt I see the port in "listening" stage? I currently have a prog running that utilizes 4661 thru 4672 (emule) but I dont see it when I run netstat.....
Linux boxes access the Net, my Win XP box sits behind it running emule..
thxs
dareino

Chain PREROUTING (policy ACCEPT)
target prot opt source destination
DNAT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpts:6881:7000 to:192.168.0.2
DNAT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpts:4661:4672 to:192.168.0.2
DNAT udp -- 0.0.0.0/0 0.0.0.0/0 udp dpt:4711 to:192.168.0.2
DNAT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpts:10240:20480 to:192.168.0.2
DNAT udp -- 0.0.0.0/0 0.0.0.0/0 udp dpt:41170 to:192.168.0.2

root@server:~# netstat -nluta
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN
tcp 0 232 192.168.0.1:22 192.168.0.2:2159 ESTABLISHED
udp 65208 0 0.0.0.0:68 0.0.0.0:*
 
Old 03-30-2004, 11:59 PM   #2
eccles23
Member
 
Registered: Jun 2003
Location: Australia
Distribution: Gentoo/kernel 2.6.2
Posts: 45

Rep: Reputation: 15
nope... because there is no service running on the server that's listening on that port...

the iptables filtering happens at a very low level... it is monitoring the packet traffic and as soon as it sees headers that contain that port info, it changes it and sends it on its way again...

so netstat wouldn't know anything about it ... there'd never be a port opened on the server for it because there doesn't need to be - it's being redirected to another computer
 
Old 03-31-2004, 08:40 AM   #3
dareino
Member
 
Registered: Mar 2004
Location: S.F.,Ca
Distribution: FC4
Posts: 82

Original Poster
Rep: Reputation: 15
thanks man
dareino
 
  


Reply



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off



Similar Threads
Thread Thread Starter Forum Replies Last Post
Quick Question about listening ports nevarlen Linux - Newbie 9 06-24-2005 03:40 PM
how to minimize listening ports johnnydangerous Fedora 19 02-13-2005 03:15 PM
Perl program to list listening ports doza Programming 1 07-29-2004 01:57 PM
Listening SuSE 9 ports uniQ Linux - Security 9 01-24-2004 12:48 AM
XDM listening to ports tarballedtux Linux - Security 7 04-28-2002 05:25 AM

LinuxQuestions.org > Forums > Linux Forums > Linux - Networking

All times are GMT -5. The time now is 03:32 PM.

Main Menu
Advertisement
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration