[SOLVED] Help with router causing issues when VPN is active

danstar10

Prominent
Nov 4, 2019
10
0
510
Hi all,
I'm having some frustrations with my D-link DIR-826L router. It works perfect and has for years, but since working from home I need to use a VPN to log into my work computer. The VPN software is called Viscosity. I am plugged into the router directly with an ethernet cable.
Whenever I have this up and running it makes windows 10 think it is disconnected from the internet every hour or so (shows the no internet icon on the taskbar), BUT during this point everything still works except the spotify program on my PC (which I use all day every day) so it is pretty frustrating. Previously I was logging out of viscosity every time and reconnecting which was annoying, but that would make windows think it was online again for an hour or so.
I have found that if I change my 'Preferred DNS server address' from what is in there to 1.1.1.1 under 'internet protocol version 4 (TCP /IPv4) properties' in my home windows 10 settings it temporarily fixes the issue.
But I have to keep running this throughout the day as it drops every hour or so, and every time I open the options again the 'Preferred DNS server address' is set back to what it was before.
Now I have found if I plug my PC directly into the modem, it works no problem, but with how my apartment is laid out I need to run a cable across the floor which is not ideal.

Soooo it sounds like my router is causing some issues. Is there any way that I can tell my router to just directly link one LAN port to the modem and not do any stuff behind the scenes, or something to that affect?
Or, if anyone has any other solutions, settings in the router etc, I am open to trying anything. I am not really network savvy so appreciate any help!

Thanks in advance,
Dan
 
Solution
This has to be the vpn software. The router has no ability to make any changes in your pc. For DNS it would only change via DHCP but when you manually set it in the ipv4 settings the pc will ignore any dns it receives via DHCP. There is no other communication between the pc and the router. The vpn software does if you have configured it override the DNS. It will change it and then hopefully change it back when the vpn terminates. This is mostly done when you want to use a internal DNS server inside a company network rather than a public one.

I forget exactly what "no internet" really means. Microsoft must be running some kind of ping to some IP to determine that.

The way vpn is normally configured is all traffic is...
This has to be the vpn software. The router has no ability to make any changes in your pc. For DNS it would only change via DHCP but when you manually set it in the ipv4 settings the pc will ignore any dns it receives via DHCP. There is no other communication between the pc and the router. The vpn software does if you have configured it override the DNS. It will change it and then hopefully change it back when the vpn terminates. This is mostly done when you want to use a internal DNS server inside a company network rather than a public one.

I forget exactly what "no internet" really means. Microsoft must be running some kind of ping to some IP to determine that.

The way vpn is normally configured is all traffic is forced via the vpn tunnel other than the single IP address used to run the tunnel itself. This means all traffic should be treated the same. No individual application should work differently, all applications should pass via the vpn. You can configure the vpn application for split tunnel in many cases and then you can get all kinds of strangeness if you do it wrong.

In any case I can't see how the router can be involved. What it should see is a single session from your PC going to a single remote IP address. This is the vpn tunnel itself and since it is encrypted the router has no idea what is inside the data packets. It can't see dns or traffic to spotify or to some internal web server. All it does is blindly substitue the public IP for the private IP on your PC and forward the traffic.

I can't explain why it would work on the modem. The key difference is when you connect to the modem you likely are getting a public IP address. The VPN software may run differently when it has a public IP.

I really hate pc vpn clients. So many things they mess up so I only run vpn on the router itself.
 
Solution
So two things are going on here--one is that your company's IT dept sucks and two you're bypassing their security which could get you in trouble.

The reason you can't reach spotify is because when you connect via the vpn, it is a 'full tunnel' where all your computer's network packets go to your work before going out to the Internet or anywhere else. This is by design as it is supposed to prevent 'man in the middle' and other type of attacks.

Unfortunately, because your company's IT dept sucks (or is just so strapped right now that they have to run this way), they are allowing your personal system to connect to the corporate network via the vpn--a big no-no since anything bad on your system can now attack your work or vice versa. Typically work will give you a corporate system that's locked down and secure before allowing this type of access.

Now, because your system is your own and isn't locked down, you are able to alter the dns server, which allows spotify server IPs to be resolved again. If your company's IT was competitent, they would block spotify's IP block, not just name resolution. So bad on you for circumventing the security and bad on the company for such wimpy security.

Now, as for why this all works correctly when you're connected directly to the modem--good question. I think again it has to do with dns servers, especially if your router is trying to 'proxy' and be the dns server for the network. Technically, this shouldn't cause any issues, but everything has bugs and this is how bugs show up.

So bottom line the reason you're having this problem is the vpn client and you have found the only solution, which is to change the dns resolution. The only other way to do it would be to add an entry in your system's local HOSTS file.

But instead of this bandaid solution, I would simply use a phone or other device to play the music. This way, this is not on the vpn and doesn't compromise your company's (pitiful) security.
 

danstar10

Prominent
Nov 4, 2019
10
0
510
Thanks for your reply guys.

Hmm interesting you say the security is terrible, there are definitely things that need to be very secure on the servers....

Strange that both of you are still unsure why the router causes the problem, but it definitely seems to be the case. SamirD, when you say 'The only other way to do it would be to add an entry in your system's local HOSTS file. ' what would I need to do to implement this as I would like to give it a try?

Cheers
 
Hmm interesting you say the security is terrible, there are definitely things that need to be very secure on the servers....

Strange that both of you are still unsure why the router causes the problem, but it definitely seems to be the case. SamirD, when you say 'The only other way to do it would be to add an entry in your system's local HOSTS file. ' what would I need to do to implement this as I would like to give it a try?

Cheers
Which is even more scary with ransomware and corporate targeting on the rise.

To use the hosts file, try these instructions (don't download the recommended program, just use notepad):