Is Double VPN untraceable?

Should you double VPN?

If you have two VPN tunnels on your network, does it improve your security if they are encrypted with different keys or should you use the same key for both?

I've seen contradictory posts but nothing conclusive. Thanks in advance. @voxferal. Your host is only secure if the keys are the same. The fact that you are using two keys is going to cause things to get messy.

The most common situation is when the main router (gateway) is compromised. If the main router is compromised and your second VPN is compromised, then every device that uses the other VPN will be compromised.

You can do what most people do. Keep them separate so that even if a device is compromised, the other remains unharmed. You can configure each system individually and not share a secret key between them. This means that any one of the services could be compromised without damaging the other.

However, there are advantages to keeping them in sync. A compromised server can cause problems for devices that share the same encryption key. If the compromised server can decrypt and encrypt all the traffic, then all the other devices that share the same key will be easily compromised.

For this reason, it is good to have a separate key for each VPN client. This allows you to monitor and audit the key as well as the activity and access logs for each.

The second VPN is only as secure as the key used for it. The best practice here would be to have separate keys and keep them in sync manually.

@Voxferal. I agree with you on the first part of your answer.

But if I have say a server which has an internal IP address of 1.2.3.4 on my home network and I use OpenVPN on the server, and I then configure two clients to use the same private key which is used on the server; isn't this still a problem? Do I need to ensure the private key is unique to the server and not to any client?

So now imagine that my home server gets compromised and an attacker is able to access the local network in order to view the files on the server, is that attacker also able to view my encrypted data? And when I use multiple clients does that mean that those clients may share the same private key?

Can I use 2 VPNs at the same time?

I want to be able to connect to 2 servers in 2 different countries from my home. I was thinking about using a dual router with 1 wifi and 1 ethernet cable for each location. I would then connect to each location via the ethernet and use a private IP address for each location. Is this possible and how could I go about doing this?

Yes, you can have as many VPN connections as you like. It does not matter whether those connections are on different routers or a single one.

The only limitation is that you need to have one main network (the one that you use for accessing the internet) and the other one should be an isolated network. If you have two routers, you can also connect them to your main network. This way they would act as a secondary router.