ssh/scp on computer hooked up to router

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12-09-2005
spencerf

ssh/scp on computer hooked up to router

I was wondering if anyone could give me some advice on ssh/scp stuff on a computer I have at home hooked up to a linksys router. For example when I'm home and I have my desktop hooked up to router through ethernet cable and my laptop running wireless I can transfer stuff easy through the routers ip of 192.blah blah blah. But when I'm away with my laptop I can't connect to desktop. I tried finding out ip of desktop by going to "whatismyip.com" and if gave me an ip address. Then I when I was away I tried using ssh.

first I started ssh on my desktop. /etc/init.d/sshd start
started it on my laptop when I was there
then I: ssh 242.192.132.13 -l bob

that isn't the exact ip but you get the point. And the cursor would just blink for a while and then no connect. So is my problem a wrong ip address or trying to run through router or maybe my commands are wrong its been a while since I used ssh. I have read the manual for ssh and scp and these have not helped so far and to be honest are quite dense I really just wanted to access my computer for an experiment for future uses.

Thanks for all your help.
12-09-2005
AndrewB

if you have got the correct ip you need to port forward from the router

port forward all requests to port number 22 to your desktops, internal ip

may be under virtial servers on the linksys
12-09-2005
spencerf

alright I'll try that. I thought that it would already be enabled if I could use ssh within my localnetwork itself but maybe not. I'll report back if this works. Gotta go find another place to get internet to try it out.
12-09-2005
davebardsley

You can test your router's firewall configuration by connecting to your router's WAN IP from within the LAN. For example:

Router:
WAN IP: 21.220.110.8
LAN IP: 192.168.0.1

PC:
eth0 IP: 192.168.0.100

Router firewall rule: forward all WAN TCP connections port 22 to the "private" LAN IP 192.168.0.100 port 22.

From the PC test it out with:

Code:

$ ssh user_name@21.220.110.8
12-09-2005
sdousley

Quote:

Originally Posted by davebardsley

You can test your router's firewall configuration by connecting to your router's WAN IP from within the LAN. For example:

Router:
WAN IP: 21.220.110.8
LAN IP: 192.168.0.1

PC:
eth0 IP: 192.168.0.100

Router firewall rule: forward all WAN TCP connections port 22 to the "private" LAN IP 192.168.0.100 port 22.

From the PC test it out with:

Code:

$ ssh user_name@21.220.110.8

Wont necesdarily work with a router.... accessing my external IP with my D-Link router failed COMPLETELY, and accessing the WAN ip with my linux router doesn't re-forward requests back to my PC internally
12-13-2005
davebardsley

sdousley

Quote:

Wont necesdarily work with a router.... accessing my external IP with my D-Link router failed COMPLETELY, and accessing the WAN ip with my linux router doesn't re-forward requests back to my PC internally

My D-Link DI-604 "out-of-the-box" (or after a reset) has only the following firewall rules enabled: WAN ping, default allow, and default deny. With the addition of a single firewall rule to forward port 22 to the specified machine

Code:

WAN,* LAN,192.168.0.100 TCP,22

one can SSH from the specified private IP address out to the router's WAN IP and have said connection forwarded back to the private machine. It works for me, and it will work for you unless you have higher priority firewall rules implemented. Try it and see.

Judging by the nature of this thread, and the implied experience of the originator I suspect that s/he will only have the standard firewall rules enabled, and I also assume that aside from insignificant syntax variations, his router and my DI-604 to behave similarly: either or both of my assumptions could be in error; I believe my suggestion will work.

BTW spencerf: Check out http://www.portforward.com. I also strongly suggest that you disable your router's ping from WAN port if you haven't' already. This will make your IP slightly more stealthy despite port scanning tools that don't rely on ping responses. Just one more defense in the overall security strategy.
12-13-2005
spencerf

ok thanks for all the advice everyone. School has ended for this semested so I'm not on an outside network right now but I'll try when I get back or go to a coffee shop or something. Thanks again. Will update when I have more info.