How to Set up a VPN on ASUS Routers with Surfshark VPN

What is the use of configuring the OpenVPN client on the router?

Although VPN providers like Surfshark VPN have specific programs for Windows, Linux and Mac PCs, as well as apps for Android and iOS, it is possible that we are directly interested in configuring the VPN on the router. The configuration of the router in VPN client mode is very simple, but we must follow certain steps and recommendations to maintain our privacy, some of the reasons for putting the VPN on the router, and not on the end devices, are as follows.

We don’t need to install anything

The first strong point of this method is that we will not have to install any program or app on the final device, that is, we will not have to install on our PCs or Macs or on our smartphones or tablets the Surfshark program or app or any another provider. Any device connected to our local network will automatically surf the Internet through the VPN.

Lets you choose which computers go through the VPN and which do not

Thanks to the routing policies, we can choose which devices we want to navigate through the VPN , and which ones we want to navigate directly through our operator without first going through the VPN. In the configuration menu itself, we must indicate the source private IP addresses that we do want to go through the VPN tunnel, and the rest will navigate without this layer of protection.

Allows Smart TVs, consoles and other devices to use VPN without installing anything

Normally, Smart TVs, consoles and other devices such as IP cameras do not allow the installation of any program or software to make use of the VPN services. Well, you will have to do it directly on a PC, smartphone or tablet, not being able to do the same on your Smart TV, for example.

When configuring the OpenVPN client on the router, we can choose that the private IP address of the Smart TV accesses the Internet via VPN, and the other devices in our home do not. With routing policies we can decide where we want traffic to flow.

We will not have to wait for the VPN connection to be established

If we use the programs or apps to use the VPN, we will always have to wait a few seconds to establish communication, when using it directly on the router, the VPN connection will always be active and working, so we will not have to wait for anything to be able to use it.

Once we have seen the advantages of using a VPN on our router in OpenVPN client mode, let’s see how we can do it with Surfshark VPN .

Get the configuration file and credentials in Surfshark VPN

The first thing we have to do is enter the official website of Surfshark VPN , register and buy the subscription to the VPN service. If we buy the subscription of 1 or 3 years, we can request a refund within the first 30 days in case we do not like the operation of this service. Prices are as follows:

• If you buy the 1-year subscription, the price is € 3.45 per month.
• If you buy the 3-year subscription, the price is € 1.69 per month.

As you can see, the prices are really competitive, this VPN is one of our favorites for price, performance and possibilities.

To start the session we must click on the top right in « Start session «.

We enter our user credentials, we have created these credentials when we have purchased the VPN subscription.

In the main menu of ” My account “, we will have to click on ” Devices ” to directly access all the software, apps, and different ways of making use of the VPN services of Surfshark.

To configure the OpenVPN client on ASUS routers, we must go to the ” Advanced / Router ” section:

At the top we will find some tutorials to configure the OpenVPN client on different routers, for example, we have tutorials to configure it with DD-WRT, Tomato firmware, and also with AsusWRT that ASUS routers use officially.

At the bottom, we can see the different OpenVPN profiles with .ovpn extension that we can download. Depending on where we want to connect, we will have to use some configuration files or others. The system automatically recognizes (by our public IP address) that our geographically closest OpenVPN server is Madrid, but we can choose the one we want.

If we click on Madrid, we can download the OpenVPN configuration, both if we use the protocol of the TCP transport layer, as well as UDP. It is recommended to always choose UDP since it will provide us with a higher performance in terms of download speed, upload speed, and it will also improve the latency of the connection somewhat.

Once we have downloaded the .ovpn file to our computer, at the bottom we will have to use the service credentials. This OpenVPN configuration file uses a CA and tls-auth to avoid Man in the Middle attacks and to be protected against possible attacks, but the authentication method with the OpenVPN server is based on username and password to facilitate configuration.

This user and password will have to be used later on the router, therefore, it is recommended to copy it in a notebook, to later copy and paste, or to do it directly from the web since we will only have to do it once. These credentials are the same for all OpenVPN servers available in Surfshark, so you won’t have to change those credentials.

Once we have downloaded the configuration from the official website, and also the access credentials to the VPN service, we proceed to configure the ASUS router in OpenVPN client mode.

Configure the OpenVPN client of ASUS routers

The router we have used is the ASUS RT-AC88U with the latest firmware version Asuswrt Merlin , since this firmware allows us to carry out routing policies, and choose which devices we want to access the Internet via VPN or directly.

The first thing we must do is make sure we have an Internet connection, we go to the menu of « VPN / VPN Client / OpenVPN «:

This menu is where we will configure everything related to the OpenVPN client:

• Select Client Instance : client1. We leave it as default, since this firmware allows you to configure several OpenVPN clients simultaneously.
• Automatic Start Boot time : we can start the VPN connection when we restart the router, this configuration is necessary if we always want to have the VPN tunnel established.
• Description : we can put a description to the VPN client that we are configuring.

In the “Browse” button is where we will have to click to later find and load the .ovpn configuration file that we have downloaded from Surfshark. Once examined, we click on “Load”.

Once the configuration is loaded, we can see that all the configuration options available in the ASUS router have been automatically filled in, however, we recommend that you make some changes that we will explain below.

For the VPN to work, we will have to enter in the “Username” and “Password” section our VPN access credentials, which were at the bottom.

Once we have applied the changes by clicking on “Apply” at the bottom, we click on “Service State” to start the OpenVPN client and connect to the server correctly. We can see that it will give us a local private IP address, and also the public IP address with which we will go to the Internet.

In these moments, the VPN is already working perfectly and we can surf the Internet with another public IP.

Recommended changes we can make

Some recommended changes that we must make, is to change the “Accept DNS Configuration”, it is recommended to set it to “Exclusive”, to use the DNS of the VPN tunnel itself and not external ones or those of our operator, to avoid any data leakage.

It is also highly recommended to configure the ” Force Internet traffic through tunnel ” option, and set it to ” Policy Rules (Strict) “, and click ” Block routed clients if tunnel goes down “. These options will allow us to leave certain computers or the entire network offline, in the event that the VPN connection drops, in order to protect our privacy.

At the bottom, we can add a maximum of 100 rules. If we want a certain PC to always surf the Internet via VPN, we must put something like this:

If we want the entire private subnet to work through this VPN tunnel yes or yes, we must put 192.168.1.0/24, indicating the subnet mask, and then clicking on “add” and “Apply” changes.

If we go to the ASUS router system registry, we can see that communication with the VPN has been established perfectly and without problems.

Once we have already configured the ASUS router in OpenVPN client mode with the Surfshark VPN service, we proceed to check its performance.

ASUS router speed in OpenVPN client mode with Surfshark VPN

The first thing we are going to check is that we are browsing the Internet with a public IP address of the OpenVPN server where we have connected, as you can see here:

We have carried out a speed test via cable of our connection, and the values we have obtained are the following:

When using the OpenVPN client on the ASUS router, the throughput is approximately 60Mbps symmetric, this is because all traffic is encrypted / decrypted, and the router’s CPU is working hard to provide the best performance. If you use a more powerful router like the ASUS RT-AX88U, GT-AX11000 or any other, the speed you will get will be clearly higher.

If we use this same VPN directly with our computer and using the VPN software, the performance is around 120Mbps, a very good speed considering that security is maximum in communication. These speeds are the typical ones that we achieve using these services.

If you are going to use 4K streaming services, you can do it without problems since the bandwidth of 60Mbps is more than enough to use up to 2 screens simultaneously in your home.

We recommend you to access the official website of Surfshark VPN where you will find all the details about this VPN, and also how to download its programs / apps directly to the final devices.