i just setup a linux fedora server at home, and would be able to ssh from another pc within my home network. However, when i tried to telnet to my server outside my home network, it wouldn't be able to reach it. I have my own domain name connecting to the specific ip of my server. Would anybody tell me why?

Does ssh connect outside your home network? Check your firewall/routing software to make sure that telnet and ssh connections are actually being sent to your home server. Another piece of advice: don't use telnet. The fact that it's plaintext and completely unencrypted means usernames and passwords are being sent out in the clear. Whenever you're connecting to a server across the internet, do yourself a favor and make sure to use ssh whenever it's available.

Does ssh connect outside your home network? Check your firewall/routing software to make sure that telnet and ssh connections are actually being sent to your home server. Another piece of advice: don't use telnet. The fact that it's plaintext and completely unencrypted means usernames and passwords are being sent out in the clear. Whenever you're connecting to a server across the internet, do yourself a favor and make sure to use ssh whenever it's available.

thanks, I am actually using ssh and just happen that i typed telnet, sorry about the confusion.
I don't have firewall and may i ask how do i check if my ssh is connected outside my home network? My router gateway is 192.168.1.1, and i did Lan setup to make my server to have a static ip 192.168.1.5--> which is what i set to my dns (however, the dyndns.com auto detector detects another ip, i have to manually change it to 192.168.1.5 so i can do ssh at home ) but when i tried to ssh at school, it said unreachable.

Well, you need to setup port forwarding on your router. Most common routers such as Linksys and D-Link have this feature; simply forward all outside (WAN) traffic that's on port 22 to 192.168.1.5 (also on port 22). At the moment you're trying to ssh into your router.

Here's another problem:

"however, the dyndns.com auto detector detects another ip, i have to manually change it to 192.168.1.5 so i can do ssh at home"

dyndns is detecting your "public" ip address, which is the one that you would use to connect to your home network from the internet side of thigns. You'll want to use the one that dyndns autodetects, which will get you to your router, and in your router, you'll set up port forwarding to forward SSH on the public IP to the SSH port on that server inside your network.

The problem with this is that you won't be able to use that dyndns hostname to connect from the local network. Actually... you SHOULD be able to do it that way, you're just going out to the internet and coming back in. Yeah! that should work as long as your dyndns hostname is pointed to the public IP and your router is routing SSH traffic to the 192.168.1.5 IP on your local network.

I hope that isn't too confusing... I'm never good at explaining network routing stuff :)

-G

thanks everybody, I can connect now!

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