Listening for incoming connections

vital_101 · 09-20-2005, 01:22 PM

Hi,

I'm using Mandriva 10.1 on my PC, and I want to be able to access it remotely. Is there anything special I need to do to make my computer listen for incoming connections (of the telnet type)? I'm using a cable modem, split through a router to connect to the internet. Will this be a problem? If you need any more information, just ask and I'll see if I can provide.

Thanks,
Vital_101

Matir · 09-20-2005, 02:06 PM

I strongly suggest you install OpenSSH, if not already installed, and use SSH instead of telnet as its encrypted. Then, configure your router to portforward port 22 to the Linux box in question.

vital_101 · 09-20-2005, 02:13 PM

Okay, I can install OpenSSH, but I'm not certain how to go about configuring my router. I'm using a belkin wireless router (except I'm connected through a Cat5 cable since I couldn't get my wireless to work). I'm completely new to the configuring of routers. Any help in that area would be great. Thanks.

/vital_101

Matir · 09-20-2005, 02:20 PM

If you can give me a specific model number, I'd be happy to look in the manual and refer you to the appropriate directions. It's often also called "Application Forwarding" with some routers.

vital_101 · 09-20-2005, 02:38 PM

the model number is F5D7230-4

Matir · 09-20-2005, 04:26 PM

On page 70 of the printed manual, it describes "Internal Forwarding". From your router's configuration, you'll need to select Firewall -> Internal Forwarding from the menu on the left side. Select enable, add a description (like "SSH"), set the port range to 22 to 22, protocol TCP, and set the private IP address to that of your Linux box. Private port should also be 22 to 22. For reference, the manual can be downloaded from Belkin.

vital_101 · 09-20-2005, 04:31 PM

Thanks for all the help. To connect to my linux box now, do I type in my linux box ip address, or the ipaddress that I get from going to someplace like http://whatismyipaddress.com ?

Matir · 09-20-2005, 04:46 PM

To connect to it (from outside your LAN) you'll need to use your so-called "world routable IP address"... aka, the address from http://whatismyipaddress.com.

vital_101 · 09-20-2005, 06:52 PM

I have everything set up as it should be, however, I still can't connect to my computer remotely. Is it possible that my cable provider is blocking things of this sort somehow? And if so, is there anything I can do about it?

tkedwards · 09-20-2005, 08:26 PM

Quote:

Is it possible that my cable provider is blocking things of this sort somehow? And if so, is there anything I can do about it?

Its possible but unlikely - most cable providers (including mine

) block things like HTTP and SMTP. You can easily switch ssh to run on another port, in fact I'd recommend it as it means you won't suffer from all those password brute-force attempts. To do that edit /etc/ssh/sshd_config and change 'Port 22' to 'Port xxx' where xxx is some port number.

Another thing to check is have a look in the file /var/log/messages and see if there's any messages from shorewall indicating that your attempts to connect are being blocked.