Cox cable - Linksys router - SSH access via port-forwarding.

Ok, I'm not the best network guy so I need some help.

Configuration:

I have cox cable coming into a Toshiba cable modem. That connects to a
Linksys BEFW11S4 gateway/router.

I have 3 systems on my LAN: 2 Windoze boxes and a Linux box -- all with
Static IPs: 192.168.1.101,102,103

The Linux box has LAN IP 192.168.1.102

I have port-forwarding on the Linksys set to forward port 22 requests
for UDP/TCP to 192.168.1.102 ... I also have "Block WAN Requests"
disables on the advanced page for router setup.

My router's status page says my "WAN IP" is 192.168.251.103 ... and if
I SSH to that IP, voila -- it works fine. I can also SSH directly to
192.168.1.102 ... so the ssh daemon is working as advertised.

Here's the tricky part... www.whatismyip.com says my "external" IP
address is 70.162.42.201... and if I SSH to that IP I get a timeout...
My router log doesn't show any incoming requests so I don't think I'm
even reaching it.

If I SSH (from work say, somewhere outside my LAN) to 192.168.251.103
(what the router says is my WAN IP) I get a timeout (can't find the
IP).

So, ... help?! Any idea what's going on? Somehow my router thinks I
have one WAN IP and the rest of the world thinks I have another. What
am I missing?

Rick

On 12 Nov 2005 13:43:05 -0800, Earnric wrote:

> Ok, I'm not the best network guy so I need some help.
>
> Configuration:
>
> I have cox cable coming into a Toshiba cable modem. That connects to a
> Linksys BEFW11S4 gateway/router.
>
> I have 3 systems on my LAN: 2 Windoze boxes and a Linux box -- all with
> Static IPs: 192.168.1.101,102,103
>
> The Linux box has LAN IP 192.168.1.102
>
> I have port-forwarding on the Linksys set to forward port 22 requests
> for UDP/TCP to 192.168.1.102 ... I also have "Block WAN Requests"
> disables on the advanced page for router setup.
>
> My router's status page says my "WAN IP" is 192.168.251.103 ... and if
> I SSH to that IP, voila -- it works fine. I can also SSH directly to
> 192.168.1.102 ... so the ssh daemon is working as advertised.
>
> Here's the tricky part... www.whatismyip.com says my "external" IP
> address is 70.162.42.201... and if I SSH to that IP I get a timeout...
> My router log doesn't show any incoming requests so I don't think I'm
> even reaching it.
>
> If I SSH (from work say, somewhere outside my LAN) to 192.168.251.103
> (what the router says is my WAN IP) I get a timeout (can't find the
> IP).
>
> So, ... help?! Any idea what's going on? Somehow my router thinks I
> have one WAN IP and the rest of the world thinks I have another. What
> am I missing?
>
> Rick

Sounds like your cable modem is also a NAT/Router gateway device which is
assigning the non-routable private address 192.168.251.103 to your router.
This private address can not be routed to from the Internet. The whatsmyip
reported address is the public address of your modem/NAT/Router device. You
will need to forward port 22 in that device to your ssh computer. Maybe try
setting your router to act as a switch and let the modem/NAT/Router do the
port forwarding. Or turn off the NAT/Router in the modem if possible.

Hey Bob... that sounds like what's happening.

Unfortuneately, I can't seem to access the html/config pages on the
modem. They are password protected and cox says they don't have the
password. The modem documentation says that only the cable provide is
'supposed' to access the config pages.

I think you've diagnosed it, now I just need to get the damn modem to
forward port 22 to my router (which is currently configured as a
gateway -- should I switch it to router mode?)

Thanks again.

No luck in finding out how to configure the router... Anyone know how
to configure a Toshiba PCX2200 cable modem? The documentation at
Toshiba says the cable company does it... but there must be a way.

R