topic Re: Cannot access home network from internet in Broadband

Cannot access home network from internet

midders — Mon, 09 Oct 2023 11:51:46 GMT

Hi there

My router died recently and was replaced by a talktalk engineer with a Sagemcom Fast 5364.

- I have recreated the port-forwarding rules that I had on the old router, but cannot get anything through the router from the wider internet

- DMZ on the router doesn't work at all (invalid ip address) no matter what I try

- if I enable respond to ping in the firewall, I can ping the router successfully using my no-ip hostname

- the services I am trying to access are all working fine inside the home network

- I have tried disabling all firewalls on both server and router as well as VPN services

After spending over an hour on a support chat this morning with zero progress, I am out of ideas, other than a faulty router and talktalk won' replace it because the broadband connection is working.

Any ideas?

Slainte

midders

Re: Cannot access home network from internet

Debbie-TalkTalk — Mon, 09 Oct 2023 11:57:18 GMT

Hi midders

I'm sorry to hear this.

Can I just check, have you tried factory resetting the router using the pin hole reset for ten seconds?

Re: Cannot access home network from internet

KeithFrench — Tue, 10 Oct 2023 21:04:25 GMT

If you want to give me some screenshots of the PF rules that you have created, I will check them for you.

Re: Cannot access home network from internet

Debbie-TalkTalk — Wed, 11 Oct 2023 05:42:59 GMT

Hi midders

Do you still need help with this?

Re: Cannot access home network from internet

midders — Wed, 11 Oct 2023 14:30:32 GMT

Thanks for the offer, Keith, but I've been a computer geek for over 40 years and I'm pretty confident the rules are good. 🙂

Just reset the router via the h/w button and now I can't even access the web interface. I can connect to the wireless network, but attempts to access 192.168.1.1 just time out...

Re: Cannot access home network from internet

Debbie-TalkTalk — Thu, 12 Oct 2023 05:58:44 GMT

Hi midders

Would you like me to send a replacement router?

Re: Cannot access home network from internet

midders — Thu, 12 Oct 2023 12:15:07 GMT

Yes, please.

Re: Cannot access home network from internet

Debbie-TalkTalk — Thu, 12 Oct 2023 12:37:55 GMT

Hi midders

Thanks for your reply.

The router is on its way, please allow 24-48hrs for this to arrive.

Let us know how you get on.

Debbie

Re: Cannot access home network from internet

midders — Thu, 12 Oct 2023 12:38:58 GMT

Thabk you, I will keep you posted.

Re: Cannot access home network from internet

Debbie-TalkTalk — Thu, 12 Oct 2023 12:53:08 GMT

Hi midders

Thank you 🙂

Debbie

Re: Cannot access home network from internet

midders — Sat, 14 Oct 2023 18:49:59 GMT

I've received the new router, thank you. However, it is behaving in exactly the same way.

- DMZ just doesn't work (invalid ip address every time)

- this time I left uPnP turned on and my deluged server created its own port forwarding rule, which works fine for local access

- I can ping the router remotely using my no-ip dyndns hostname

- all attempts to remotely access the deluged server, or any others just time out

I think this must be a fault in the router firmware. I have bought a Draytek router and will post back when I've finished configuring it, as it is a bit more complex than the talktalk one.

I will return one of the talktalk routers shortly.

Slàinte

midders

Re: Cannot access home network from internet

KeithFrench — Sat, 14 Oct 2023 20:39:06 GMT

That has proved that it is not the router then. Not working in the DMZ is a big indication that something you are doing is wrong, or your testing is falling foul of NAT Loopback.

If you want help, as I asked originally, please can you send me a screenshot of the pf rule that you are using and I will help you until resolved.

Re: Cannot access home network from internet

midders — Sat, 14 Oct 2023 23:45:51 GMT

Here's a screenshot of my port forwarding rules; I normally disable uPnP but I left it on and you can see the rule it generated for my deluged server. These rules worked fine on the old router (with firewall set to high). I currently have the firewall set to low to rule it out as a problem.

Slàinte

midders

Re: Cannot access home network from internet

KeithFrench — Sun, 15 Oct 2023 10:37:31 GMT

Hi @midders

I would strongly recommend that you disable UPnP as it is very insecure.

There is nothing else wrong with the PF rules. Please ensure that the device is not in the DMZ any more and set the firewall back to medium. I will double check that these ports forward OK this afternoon.

Tell me more about this server. What OS is it, does it have a firewall and how are you testing this?

Re: Cannot access home network from internet

KeithFrench — Sun, 15 Oct 2023 12:03:24 GMT

Hi @midders

These are the port forwarding rules I set up:-

My PF rules

From here I tested both TCP & UDP port 53665, whilst opening port 22 as either TCP or UDP and they worked the first time. I have only shown the results for the TCP test, as I use my own testing application for UDP:-

TCP port 53665 result

Then I tested TCP port 57518 and that was fine as well:-

TCP port 57518 result

Please can you respond to my questions concerning your server, when you get a chance?

Thanks.

Re: Cannot access home network from internet

midders — Sun, 15 Oct 2023 14:16:34 GMT

Thanks for your efforts, my server is running Ubuntu 22 LTS, has dual NICs (...94, and ...104) one setup for VPN and the other without for remote access. I'm running ufw firewall and surfshark VPN but have tried disabling both to get remote access working.

It was all working perfectly before the router died, and the only thing that has changed is the router... or are there other settings that talktalk can tweak behind the scenes?

The router doesn't recognize the dual NICs correctly, giving them both the same IP, but the old one did the same thing and still worked. The server shows the correct IPs.

I played around with the Draytek router last night and am about ready to test it. Fingers crossed.

Slàinte

Mark

Re: Cannot access home network from internet

KeithFrench — Sun, 15 Oct 2023 14:41:09 GMT

You will need to add rules for the ports in ufw. With the VPN is the Ubuntu the VPN server? Assuming it is, then the Ubuntu should not allocate the same IP address to different NICs. There is nothing that TalkTalk can change behind the scenes to affect this.

My first action would to rectify why the server is allocating the IP address wrongly.

Re: Cannot access home network from internet

KeithFrench — Sun, 15 Oct 2023 20:49:44 GMT

Whilst I cannot exactly replicate your setup, I will also test this on a Linux Mint installation that I have tomorrow.

Re: Cannot access home network from internet

KeithFrench — Mon, 16 Oct 2023 09:47:08 GMT

Hi @midders

I have just tried all ports in Linux Mint having first added them to the GUI version of ufw and they work fine.

Re: Cannot access home network from internet

midders — Tue, 17 Oct 2023 01:10:56 GMT

The server is a VPN client, ufw is setup for all the required ports. As I mentioned before EVERYTHING WAS WORKING FINE before the router died.

Since the only thing that has changed is the router, that has to be at fault.