How to open a port

[coper]

Hello,

As a novice on linux when I set-up my firewall on my redhat web server I just simply used entered setup at the root prompt and selected to allow port 80 and 21. How the firewall rules are set and where they are stored I don't know. So how would I open a port like 50O or 501??

Thanks

 

[krischrist]

Hi,
By default all ports are open.To see a list of ports used on your system see /etc/services. To close specific ports use either /etc/inetd.conf or use a ipchains rule.

regards
Krischrist

http://krischrist-quest.tripod.com

 

[coper]

Hi,
I have enable maximum security, via the command line
"setup" utility, and the Firewall Configuration tool. I then used customize and enabled access to HTTP,FTP,SSH.
Is there a way in the box that says other ports to allow incoming and outgoing tcp connections through port 501 for example. Or what do I enter in the /etc/services and /etc/inetd.conf files.

Thanks

 

[sarm]

Hello,

Although I have never used it you should be able to enter:
Use the following format: portrotocol.

So, if you want to allow udp packets on port 500 through the firewall, enter 500:udp. To allow tcp packets then 500:tcp

Someone else may know a better way but this is all I can suggest...

Good luck

 

[coper]

hello again,

OK I did that. Now how do I tell if port is listening for tcp request? Is there a command for this?

thanks

 

[ady2k]

You can use this command :
# netstat -a