How to check the external IP of a router? / Port forwarding thru' two routers.

Hi, our internet provider provides us with a router (R1) but would not give us the login to the control panel. We have connected our own router (R2) to their router, and connect our computers through our own router (R2).

The setting is very much like the one described in this guide: http://www.portforward.com/help/doublerouterportforwarding.htm

The ISP will configure the port forwarding on R1 for us once and once only (well, they can change it again for a "modest" fee, of course). So I would like to have R1 forward all the ports to R2, and distribute them as needed through R2.
I've noticed from the guide above that I will need to forward the ports from R1 into the "external ip" of R2. Is there anyway I can find out what that is?

Again, I've no access to the control panel of R1 (it's a D-Link DI-604 if it makes any difference), here's the info from the R2 (Linksys) control panel:
Internet IP Address: 192.168.0.164
Subnet Mask: 255.255.255.0
Default Gateway: 192.168.0.1

Router IP : Local IP Address: 192.168.1.1

Should I ask the ISP to forward the ports to 192.168.0.164 or 192.168.1.1 or some other IP address?
I can access the control panel of the R1 at both addresses.

Thank you for your time.

first off, if your ISP is using a normal DI-604, isn't there a reset button on the back you can push for a few seconds with a pencil, that will reset it's passwd?

looking at your linksys's addresses, it looks like R2's address as assigned by R1 is 192.168.0.164

R1's internal network address is 192.168.0.1

your computer's address, as assigned by R2, is 192.168.1.1

get it?

here's a shitty picture:

yourComputer[192.168.1.XXX]<--->[192.168.1.1]Router2[192.168.0.164]<--->[192.168.0.1]Router1[yourInternetIP]<--->[ISPgateway]theInterweb

that's how i understand it anyways.

also, realize that every port you open on R2 must also be opened on R1. kind of a pain in the ass.....i change my port forwarding config every couple weeks or so.

it would sure be a lot easier to be able to get rid of your ISP's router all together.

PS, welcome to DevH

Thanks a lot for the help!

I've thought of resetting the router, but since the ISP won't tell us what's the TCP/IP settings and if there's any login needed, I worry if I'd be able to get it configured right after resetting (and yeah, charges if they have to come and do it for us :/ ).

I will get the ISP to forward all ports to 192.168.0.164 and hopefully that will means we can change the port forwarding settings on R2 anytime we want

well, if the reset doesn't work, there's no harm done. if the reset does work you'll have to set the 604's settings in the same way you're setting your Linksys's settings, which is something we can certainly help you with, and might be readily available on D-Link's website.

it might be worth a shot...