A few questions about DNS !

[xkeyskored 3]

Hi all I just got AirVPN and am very happy with the service. The teams dedication to anonymity is not met by any other provider. I just have a few questions that vaguely relate to the service, but are also more general. I scoured the internet for hours trying to find answers to these specific questions but I couldn't find a direct answer from someone who knew what they were talking about. Ok, here goes:

 

1.I have come to understand that the system defaults for DNS are that it points to a LAN address, e.g 192.168.x.x for the DNS resolver. And this is because the DNS address is stored in my wireless router? Is that right? And how would I go about changing the default (if I ever wanted to.)?

 

2.If you use a vpn of any vendor, be it AirVPN, PIA or IPVanish, and use either their client software, or the openvpn gui, the system automatically changes the DNS resolver address for the period of you being connected to that VPN session. And I know that DNS leaks are when you get a thing I think is called 'split tunneling' where the DNS resolver is left as standard and even though your internet traffic is being routed through the encrypted VPN tunnel, your DNS requests are still going to your ISP. BUT, what about using a 3rd party DNS like openDNS, will any DNS resolver be routed through the VPN tunnel except the ISP's one?

 

Thanks in advance!

[eyes878 43]

Changing the DNS on the router would depend upon the router model. Try a google. The reason it is a 192.168.x.x address is because the DNS request goes to the router and then the router requests the DNS server, usually your ISP's.

 

As for the 2nd question, I'm not fully sure what you mean, or how to answer what I think you mean.

[InactiveUser 188]

Answering question 1:
Most routers can act as a DNS server/forwarder. They will forward your DNS requests to a DNS server of your choice - or, by default - your ISP's DNS server.
In most cases, people configure their network interfaces using the automatic DHCP process. With DHCP, your computer tells the router: "I want to be part of your LAN, please give me an IP address!"
The router answers: "Fine, you can have 192.168.1.39, my address is 192.168.1.1! Oh, and I can also be your DNS server!"
Your operating system will configure your network accordingly.
That's why you usually see your router as your default DNS server.

You can override that by going into your network interface's settings and manually setting a DNS server.

Answering question 2:
When you connect to the OpenVPN server, your OS will (usually) be told to use the server as its new default gateway.
From this point on, any traffic to remote IPs will go to that gateway, including DNS requests to an OpenDNS server. In this case, no leak can happen.

Of course, if your OS is configured to send DNS requests to a local address (your router), they will not be tunneled and your router then resolves the DNS requests using your real IP.

That's how a DNS leak happens, and you correctly mentioned that tools like the AirVPN client will prevent that by overriding your system's DNS settings for the duration of the VPN connection.
On the other hand, other tools like for example the Linux NetworkManager might only add the VPN's DNS server to your network configuration but not replace the default one.

[xkeyskored 3]

Sorry it took me a while to get back to this thread, been busy! Thank you for your answers and to you 'sheivoko' you answered exactly what I wanted to know there in question 2, bang on. Thanks again for the replies