How to find IP of main Router?

[integraoligist]

So this is how our internal network goes:
ISP > Main Router > Sub Router > Our PCs

I need to know how to find the IP of the Main Router for login purposes. As logging into the Sub Router shows the WAN (which is just a static IP setup by the Main Router). We can't connect a PC directly to the Main router to find the Gateways IP to login so we basically need to map this out.

Ideas?
Thanks all!

 

[abailey]

The default gateway on your Sub Router WAN port is most likely the IP Address needed to manage the main router (but not always).
That is if I am reading it correctly and the link from your Main Router is going into the WAN port of your Sub Router.

 

[integraoligist]

The default gateway on your Sub Router WAN port is most likely the IP Address needed to manage the main router (but not always).
That is if I am reading it correctly and the link from your Main Router is going into the WAN port of your Sub Router.

No, the gateway IP on the Sub router is different then the Main routers login IP.... there are actually about 25 Sub Router connected to this Main router and each Sub Router is off by 1 point.... example, Sub1 xxx.xxx.xxx.001 Sub2 xxx.xxx.xxx.002 and so on

Actually, when you pull the IP from a PC on each Sub router the public address is the WAN IP of the Sub router... so this is somehow passed through the Main Router. All of the Sub Routers connected via PPPoE through a radio which transmits to the Main Router.

 

[anotherdrew]

2 ideas ... both are fraught with issues.
1. Pull the routing table from one of the sub routers. This may require CLI access ... I don't know if your comfortable with that.
2. Try using a tracert command ("tracert google.com"). Not all devices report their IP, so it might not work.

 

[abailey]

No, the gateway IP on the Sub router is different then the Main routers login IP.... there are actually about 25 Sub Router connected to this Main router and each Sub Router is off by 1 point.... example, Sub1 xxx.xxx.xxx.001 Sub2 xxx.xxx.xxx.002 and so on

Actually, when you pull the IP from a PC on each Sub router the public address is the WAN IP of the Sub router... so this is somehow passed through the Main Router. All of the Sub Routers connected via PPPoE through a radio which transmits to the Main Router.

This is much more complex than what you said in the original message. Details like this are very helpful. More details would be even better. Did your company set this up? Is this ISP delivered? With what I can tell from the setup you described I would be very surprised if the core router (or Main Router) is not set up on a management VLAN so that people from the different sites would not have access to try to manage it. Anyway the more details you can give the better.

 

[jfreggie2]

Can you console in to the main router to get the info you need?

 

[failboat]

Can you not fix the issue of being able to connect directly to your main router? Seems like a bad setup problem.

 

[Alabalcho]

c:\users\me\> tracert -n www.google.com