How to discover a router's ip in lan?

knarh · 2024-04-23 14:17:23

Hello guys, I'm absolute noob in networks.

So, there's a second router which I want to use as a wi-fi access point, so I want to configure it somehow.

layout: isp -> first router -> switch -> other stuff
-> 2 router (wi-fi acces point)

What I need to do to get into router settings?

And can you suggest some books/guides about networks, please. because I'm feeling ashamed to ask questions like this.

Thanks in advance.

update: it works like a wifi access point, but it doesn't have password and it works as a separate "wifi network", so can it be configured to be a part of my first router "wifi network"?

Last edited by knarh (2024-04-23 14:52:50)

schard · 2024-04-23 15:31:32

If the device is on your home network, you can just scan your local network with e.g. nmap.

seth · 2024-04-23 16:44:49

it works like a wifi access point, but it doesn't have password and it works as a separate "wifi network", so can it be configured to be a part of my first router "wifi network"?

This heavily depends on the (undisclosed) router, eg. whether it supports https://en.wikipedia.org/wiki/Wireless_ … ion_system

But do you actually just want do degrade an ISP issued router to a pure modem, ie. make router #2 a client of router #1 and setup the LAN exclusively behind router #2?
Or do you want to have a split network (public/private) w/ maybe a conditional bridge?

Assuming you're not running arch as one of the routers that has strictly nothing to do w/ any client (your PC), but you want to elaborate on your final goal here for an informed comment beyond "check the router manual whether it supports WDS or any other wireless bridging/forwarding"

MS-DTYP · 2024-04-24 10:02:42

Traceroute + nmap. However, avoid using nmap on your corporate network or hotel network as this can be viewed negatively and may be illegal. It can be used only for your own network.

$ traceroute 8.8.8.8
traceroute to 8.8.8.8 (8.8.8.8), 30 hops max, 60 byte packets
1 _gateway (172.20.10.1) 3.145 ms * *
2 10.241.25.1 (10.241.254.18) 37.818 ms * *
3 10.245.25.30 (10.241.253.30) 48.510 ms **
...

10.241.25.1 should be the IP address of the second router. Alternatively, you would need to use nmap on 10.241.25.0/24 or similar.

However, these commands only reveal the IP address. To configure a Wi-Fi network, you would need to obtain the network password, which is not related to the IP address in any way. If it's a security audit and you have permission, you would need to audit 10.241.25.1 and gain access to it to retrieve the Wi-Fi password. Ensure that you do not exceed the authorized scope during the audit and that you are not auditing an ISP router without permission.

If you want to build a single Wi-Fi network using two of your own routers, you need to purchase two fancy routers and perform a complex configuration. Arbitrary routers cannot be merged into one network in such a way that they function as a single entity.

Alternatively, you can set the same network name (SSID) and password on your arbitrary routers, which will allow devices to connect to whichever network provides the better signal. Here it will be important to manually set different Wi-Fi channels on each of the routers. I recommend using channels 1, 6, 11 for 2.4 GHz ranges, or 2 + 7 + 11 or 3 + 8 + 11, etc. The same is for 5Ghz ranges. But don't expect this solution to work great.

If you own second router and its Wi-Fi network doesn't have a password, I recommend configuring it as soon as possible.

Last edited by MS-DTYP (2024-04-24 10:28:27)

Arch Linux

#1 2024-04-23 14:17:23

How to discover a router's ip in lan?

#2 2024-04-23 15:31:32

Re: How to discover a router's ip in lan?

#3 2024-04-23 16:44:49

Re: How to discover a router's ip in lan?

#4 2024-04-24 10:02:42

Re: How to discover a router's ip in lan?

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