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Old 07-29-2007, 02:32 PM   #1
ovl
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Firewall - two different installed ????


hello,

i have a redhat machine, and my admin is in holidays and not reachable, as i have to open a port, i tried this to do in plesk with IPtables, but this has no effect. i have allready all ports open, but it still blocks some.

for example: port 80 is open, when i close it in plesk it is closed, when i open it its opened. but when i open port 8080 it is closed, does not matter what i do.

so i think there is second firewall installed, how can i check this, i am a rookie to linux so i hope you could help me.

thx in advance
 
Old 07-29-2007, 04:01 PM   #2
stress_junkie
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The idea that a port is open or closed is really about whether there is an application that will respond to requests to connect to that port. For example you might not have any firewall at all but unless you have a mail server program running then port 25 will be closed. Mail servers respond to requests to connect to port 25. If you have a mail server application running then the port is open. If you don't have any mail server application running then the port is closed. Firewalls can prevent connection requests on given ports. That is another level of whether ports are open or closed. So you need to have an application that responds to connect requests on a given port before it is open, plus you must configure your firewall to permit the connect requests to be passed to the application that is listening on a given port.

As far as port 8080 is concerned I am going to guess that your web server software is not configured to respond to requests to connect on that port.

It is possible but unlikely that there are two firewall applications running on one machine, unless your system administrator likes to make things really difficult. There are two kinds of firewall applications that run on Linux. The first kind just configures iptables and then it exits. The second kind runs a daemon that intercepts network traffic and decides what to do with each packet. So it is possible to have more than one firewall but it is unlikely.

Last edited by stress_junkie; 07-29-2007 at 04:08 PM.
 
Old 07-29-2007, 04:04 PM   #3
ovl
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no i have a shoutcast server installed.

with lynx the admin interface is on the local machine reachable, but from the outside i can not get it, also the internal streaming works!

i have now opened all the ports but i can not get through to the admin interface from 3 different pc's.
 
Old 07-29-2007, 04:12 PM   #4
stress_junkie
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When you connect to a network application on the same machine that is running the application then you are connecting through the localhost network connection. That is enabled by the imaginary network connection called lo. When you try to connect to the application from another computer then you will be using the real network card. That is probably configured as eth0.

If you turn off your firewall software completely you will be able to see if the problem is with the firewall or if it is a case that the shoutcast software is not listening to the network for connection requests.

I am not familiar with Red Hat but it is my understanding that they have system administration applets for this sort of thing. There should be a system administration applet to do what you are trying to do.

Last edited by stress_junkie; 07-29-2007 at 04:15 PM.
 
Old 07-29-2007, 04:41 PM   #5
ovl
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i have delete iptables.... but nothing changed.

with lynx i have access, but from any other machine i dont get on it!

please anybody who can help me????
 
  


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