Hello, I’m new to Linux (openSUSE) and having a problem with ICS :).
Description:
PC1 has installed Windows Vista and is connected via WLAN with a Router (incl. Modem) and PC1 is connected via LAN with PC2 which has running openSUSE 11.0.
PC1 WLAN (Vista):
IP: 192.168.178.20
Default Gateway: 192.168.178.1 (Router)
DNS: 192.168.178.1
PC1 LAN (Vista):
IP: 192.168.178.30
PC2 LAN (openSUSE):
IP: 192.168.178.31
Default Gateway: 192.168.178.30
DNS: 192.168.178.30
This works fine, so the internet works on PC2 and PC1 ;).
But my Problem is I can’t ping the Router at PC2.
And PC2 has the same intern IP at the Router as PC1.
But my goal is to have a different intern IP at the Router for PC2, is this possible? When yes, how? 
MfG CodenameReese
You have to assign a range of IP addresses for the LAN
eg:
your router may be 192.168.0.1
so you would give a range of say
192.168.0.2 to 192.168.0.4
that will give you Ip ending 2,3,4,
There should be section in your router
LAN IP Setup
and a dhcp range
and address reservation (this is the important bit) you need the MAC address of the connecting device too
Thanks for your quick answer 
The DHCP IP Range of my Router (Fritz!Box Fon WLAN 7170) is active from 192.168.178.20 up to 192.168.178.200 so all my addresses (PC1 and PC2) are in that range^^
There is also a section for static-routing tables!?
And I don’t find anything like address reservation where I have to put the MAC-address of the LAN-Device (PC2).
MfG CodenameReese
You could download a manual for your router (whatever it is)
You may find help here
PortForward.com - Free Help Setting up Your Router or Firewall
It just needs a bit of research on your part.
Tell us the make and model of the router if you like and we can look it up for you when we have time
My Router is a Fritz!Box Fon WLAN 7170 as I said
And I think this address reservation is not possible with my routers original firmware^^ But I didn’t understand the need of this? There is no such IP besides the one of PC2.
The internet works on PC2 but i can’t ping the router from it, and the router configuration site isn’t accessible.
And since I connect PC2 via PC1 with my Router he doesn’t recognize a different intern IP than PC1 has got, e.g. my PC1 has IP 192.168.178.20 at my Router so PC2 connects with the same, I think. Because I can’t see any other at the Router.
MfG CodenameReese
Hmm nobody can help?
My Network looks something like this:
Internet -> Router (Fritz!Box) -> PC1 (Vista) -> PC2 (openSUSE)
I need to have an own intern IP for PC2, to communicate with PC2 through other PC’s. If I would try it now, I would end up at PC1, which has got the same intern IP as PC2. 
Please, help.
MfG Reese