Forgot my router's IP address

jstars · 12-02-2006, 07:28 PM

I have a linksys router that is set to act as a switch and wireless access point on my home network. The problem is that I forgot what IP address I gave it and therefore cannot access its web based configuration. It is not the default 192.168.1.1. How do I find it? I tried

Code:

ping -b 192.168.0.255

(a broadcast ping), but it just sits there getting no response, not even from the WinXP machines on my home network. What am I doing wrong?

Quakeboy02 · 12-02-2006, 07:41 PM

If you hold the reset button in for 30 seconds, it will set the router back to defaults. Then you can reconfigure it. Unless you have a good reason not to, it's probably a good idea to use 192.168.0.1 as your router IP.

nuxrl · 12-02-2006, 07:55 PM

Is the router still functioning?

jstars · 12-02-2006, 08:22 PM

The router is definitely still functioning because that is how I get from my client PCs to my gateway (which is a clarkconnect linux server) and out to the internet.

My network looks like this:

Internet
|
|
Gateway/Server 192.168.0.1
|
|
Router/Switch 192.168.?.?
| | |
| | |
PC1 PC2 PC3

I know my router's ip address isn't 192.168.0.1 because that is the IP address of my gateway/server. I did consider doing a reset, but thought there was a more "elegant" way of finding out what the ip address was. Why is 192.168.0.1 a bad idea?

nuxrl · 12-02-2006, 08:30 PM

From the linux box, try,

Code:

#arp -a -v

Quakeboy02 · 12-02-2006, 10:09 PM

Sorry. My response was prejudiced by my own configuration. I have a single router/gateway. It simply never occurred to me that you wouldn't have the same. d'oh

alienux · 12-02-2006, 10:25 PM

Quote:

Originally Posted by jstars

The router is definitely still functioning because that is how I get from my client PCs to my gateway (which is a clarkconnect linux server) and out to the internet.

My network looks like this:

Internet
|
|
Gateway/Server 192.168.0.1
|
|
Router/Switch 192.168.?.?
| | |
| | |
PC1 PC2 PC3

I know my router's ip address isn't 192.168.0.1 because that is the IP address of my gateway/server. I did consider doing a reset, but thought there was a more "elegant" way of finding out what the ip address was. Why is 192.168.0.1 a bad idea?

It looks like the router should be the default gateway for your PCs, so if that is the case, just enter the command "route" (or possibly "/sbin/route" depending on dist. and PATH). The line that says "default" should give you the routers address, which can be used to access it.

jstars · 12-02-2006, 10:28 PM

Code:

pc3:/home/alfred # arp -a -v
gateway.clarkconnect.lan (192.168.0.1) at 00:40:F4:EB:CB:58 [ether] on wlan0
Entries: 1      Skipped: 0      Found: 1

jstars · 12-02-2006, 11:41 PM

Quote:

Originally Posted by alienux

It looks like the router should be the default gateway for your PCs, so if that is the case, just enter the command "route" (or possibly "/sbin/route" depending on dist. and PATH). The line that says "default" should give you the routers address, which can be used to access it.

Code:

pc3:/home/alfred # route
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.0.0     *               255.255.255.0   U     0      0        0 wlan0
link-local      *               255.255.0.0     U     0      0        0 wlan0
loopback        *               255.0.0.0       U     0      0        0 lo
default         gateway.clarkco 0.0.0.0         UG    0      0        0 wlan0

This is what my linux machine (laptop) comes up with.

alienux · 12-03-2006, 07:04 AM

Quote:

Originally Posted by jstars

This is what my linux machine (laptop) comes up with.

I misread your first post. I didn't previously catch that you're using the router as a switch, which sounds like you aren't using it's routing function, and so if gateway.clarkco is 192.168.0.1, then my last suggestion won't help.

Three questions:
-Do you have nmap installed on your PC?
-How many devices should be on the 192.168.0.0/24 network?
-Do you have an idea what the 3rd octet of the router's address is if it isn't on the 192.168.0.0 network?

It its possible that the router is on the 192.168.0.0 network, you can use nmap to discover all up hosts with the following command:

Code:

nmap -sP 192.168.0.0/24

This should return a list of pingable objects on that subnet, so if you get 5 results, and you have 3 PCs and the gateway, the 5th item should be the router.

If the router is not on the 192.168.0.0 network, and traffic is just being switched by the router, rather than routed, it will be a little tougher to figure out.

amitsharma_26 · 12-03-2006, 07:44 AM

If you have accessed that switch(wireless access point) with its changed ip from your own box or any other box then you can find it in the browser's HISTORY (if not cleared).

Otherwise NMAPing the whole Class C with -F mode will be helpfull.

Or you must have got some cd for OS interface installation with that router as well. Install it at any OS box & then it will find your routers/switches/wireless access points on its own.