Able to ping my modem but can't access management interface via browser

Installing and Using OpenWrt
1

I've got openwrt on a NanoPi R6S. Using the build from here: https://github.com/mj22226/openwrt/releases. I want to be able to access my modem via LAN-connected devices and I followed the instructions available to set that up.

I can confirm that I can ping my modem and it responds fine. Its IP address is 192.168.100.1 (my 2nd configured WAN interface is set to static IP at 192.168.100.2).

I've tried multiple browsers and devices. Incognito mode etc. 192.168.100.1 always times out. Trying to do some googling, I found someone with a similar issue where the resolution was simply power cycling the modem (it's a cable DOCSIS 3.1 modem and it is in bridge mode - I had to ask my ISP to put it into bridge mode for me).

Any ideas? It's not critical but would be nice to be able to manage my modem remotely and I can't understand why it won't let me into the management portal...

2

That device is not supported by the official OpenWrt project.

You can try the method described here:

But

if it doesn't work you need to ask the maintainer of that firmware since it is not from the official project.

3

Appreciate the response. I understand the the NanoPi R6S is not officially supported.

The link you shared is the exact instruction set I followed. Everything seems to be working as it should, given I can ping my modem's IP (which is on a different subnet than my LAN of course) and it responds fine.

But.. in any and all browsers, the connection request times out instead of showing me a login page as it should. Just looking for any insight from any others that may have run into the same ... I don't believe this to be firmware dependent but moreso something caused by my specific modem/ISP. I'm on Cogeco and my modem is a Sagemcom F@st 3896.

Also, I'm well aware that the modem's IP is usually 192.168.40.1. In fact, it was that before I got Cogeco to switch the modem over to bridge mode. Now that it's in bridge mode, its IP is 192.168.100.1. I have verified this by connecting successfully to the management interface when wired in directly to the modem. Though I will add that I've had trouble connecting again recently, even when wired in directly. Could my ISP just be blocking me from the management portal?

4

In this situation, you'd be talking about two things that are out-of-scope here:

  1. anything that is firmware specific for the unofficial version of OpenWrt that you are using would need to be supported by the maintainer.
  2. Any modem (or ISP) related issues need to be supported by the vendor (or ISP).
5

I get it. I'm posting here about it because:

  1. As evidenced by the many other posts with a similar topic, this community seems to be of the type who wants to do things like this (access their modem which is on a different subnet) and understands what I'm talking about... so even if the underlying issue is not to do with openwrt itself, I'm hoping someone has come across a similar issue and solved it / can help me.

  2. If I do indeed find a solution, it can live on to help others like me in future :slight_smile:

If that's out of line, please say so and I will delete the post. Thanks.

6

Were you sure to use https://?

7

yes forgot to mention. Trying different browsers and both http:// and https://. All time out.

Now I'm trying different static IPs (e.g. 192.168.100.150 instead of 192.168.100.2) in the 2nd wan config. Still nothing.

8

Ok. I went down to the modem and plugged in directly (after unplugging everything else), setting a static IP (192.168.100.2). This did NOT work and I could not access the mgmgt console. Again, I could ping 192.168.100.1 and it would respond find (with lower latency :wink: ) Tried all browsers, http vs. https. Tried power cycling modem while plugged in etc. Nothing.

Finally, I set my network adapter to obtain IP automatically, so I got assigned an external IP by my ISP (I think?). Then and only then could I access my modem's management console (on 192.168.100.1). I did reboot the modem after I changed the settings but I'm unsure if that was a necessary step or not.

So, given that new information. Anyone who understands more about cable modems and ISPs and networking in general have any advice for me? I'd love to figure this out, just for the principle of it.

I did find an option of "Remote Config Management" in the advanced access control settings, which was disabled and I enabled it. But... That did nothing. I can ping 192.168.100.1 and it responds (whether I'm plugged in directly or on a LAN-connected device)... but it won't load the login page for me in any browser. Fun.

And yes, this issue seems to have precisely 0 to do with openwrt.... :wink:

9

In my experience with cable modems, the only upstream interface should be dhcp (for your wan) and that's it... no need for additional interfaces to reach the modem's status/admin page. So the default OpenWrt config would work in this way. Did you try that?

10

You mean did I try to access 192.168.100.1 before I followed the instructions and created the 2nd wan instance in openwrt? Yes, I did and no joy.

Unless you mean something different by "default" config?

11

hmmm. Another clue maybe. I did just delete the 2nd wan config. Rebooted router to make sure... and.. I can STILL ping 192.168.100.1 successfully without it.

So you're right. The 2nd wan config doesn't seem necessary at all in my case. But the result is still the same. No access to console.

12

I think I gotta take this up with my ISP. But their support is so useless I'm definitely not gonna get anywhere with this... :confused:

13

Could you tell us what kind of IP address you got? Was it a public or a private address?

14

It was a public IP I'm pretty sure. Sorry, that's what I meant by "external" IP.
i.e. it did NOT start with 192.

Modem is in bridge mode so its DHCP is off. But it will give a single PC a public IP just like it will give a router a single public IP...