[Guide] Build a budget VPN with AWS Lightsail and Wireguard

What is Wireguard? According to their page, they states:

“WireGuard® is an extremely simple yet fast and modern VPN that utilizes state-of-the-art cryptography. It aims to be faster, simpler, leaner, and more useful than IPsec, while avoiding the massive headache. It intends to be considerably more performant than OpenVPN. WireGuard is designed as a general purpose VPN for running on embedded interfaces and super computers alike, fit for many different circumstances. Initially released for the Linux kernel, it is now cross-platform (Windows, macOS, BSD, iOS, Android) and widely deployable. It is currently under heavy development, but already it might be regarded as the most secure, easiest to use, and simplest VPN solution in the industry.”

I’ve been using it for about a year now and it’s very fast and lightweight indeed.

My use case was quite odd when i came to WireGuard, i was finding a way to bypass Internet Censorship in my country. Unfortunately, Medium was one of those restricted sites in my country.

Let’s put the politics aside. First, i rented a Ubuntu VPS on AWS located outside of my country. Lightsail was a good choice because it provides a machine which is strong enough and cheap enough for me to effort. It has 2 GB of RAM, 2 vCPUs and 60GB SSD. It costs me only $10 a month. In my case, i also use it for other purposes, if Lightsail is the only thing you use, you should choose the $3.5 plan which is cheaper and more than strong enough for Lightsail hosting.

Server side configuration (Ubuntu)

Installing Wireguard

First, we can install Wireguard by using the following commands

sudo apt update 
sudo apt install wireguard

Generating public and private key

After that, we have to generate private key and public key for Wireguard asymmetric validation.

First, for the private key we will use the following commands

wg genkey | sudo tee /etc/wireguard/private.key 
sudo chmod go= /etc/wireguard/private.key

And this command for public key, note that we generate the public key using the private key from the last step here.

sudo cat /etc/wireguard/private.key | wg pubkey | sudo tee /etc/wireguard/public.key

Find the public network interface

ip route list default

My terminal output, it could be different on your machienens5

dev ens5 proto dhcp src xxx.xxx.xxx.xxx metric 100

Creating the wg0.conf configuration file

In order to config Wireguard, we will have to create the configuration file using this command

sudo nano /etc/wireguard/wg0.conf

Then, we will modify the content in the wg0.conf file

Inside the wg0.conf file, we define the configuration for the server and client (peer). We will leave the [Peer] section for now and come back later when we finished the configuration for the Client

[Interface] 
Address = 10.8.0.1/24 
SaveConfig = true 
PostUp = ufw route allow in on wg0 out on ens5 
PostUp = iptables -t nat -I POSTROUTING -o ens5 -j MASQUERADE 
PostUp = ip6tables -t nat -I POSTROUTING -o ens5 -j MASQUERADE 
PreDown = ufw route delete allow in on wg0 out on ens5 
PreDown = iptables -t nat -D POSTROUTING -o ens5 -j MASQUERADE 
PreDown = ip6tables -t nat -D POSTROUTING -o ens5 -j MASQUERADE 
ListenPort = 51820 
PrivateKey = Your Secret created in previous step 
 
[Peer] 
PublicKey = Peer public key 
AllowedIPs = 10.8.0.2/32 
 
[Peer] 
PublicKey = Peer public key 
AllowedIPs = 10.8.0.3/32

The [Interface] sections defines the Server’s configuration and the [Peer] section defines the section that belongs to the client.

Adjusting the server network configuration

Use your favorite text editor to edit the /etc/sysctl.conf. Mine is vim, so i use this command sudo vim /etc/sysctl.conf

We only need to un-comment these lines by removing # at the beginning of these lines

net.ipv4.ip_forward=1 
net.ipv6.conf.all.forwarding=1

Firewall

From the Lightsail dashboard, we switch to Network tab and add Firewall rule for our machine. In my case, i allow all ports for both IPv4 and IPv6 for purposes other than VPN. You should allow only port 51820here if Wireguard is the only inbound connection you have.

Beside the Lightsail firewall, you will have to adjust the firewall rule in your Ubuntu instance using these commands

sudo ufw allow 51820/udp 
sudo ufw allow OpenSSH

After that, we will start the Wireguard service

sudo systemctl enable [email protected] 
sudo systemctl start [email protected]

Configure Wireguard client

In my use case, i use Windows as Wireguard Client. First, we go to this link to download the installation.

After finish installing Wireguard and opened Wireguard, we right-click the empty panel in the Tunnels tab and select “Add empty tunnel…”

The good thing with this UI approach is that it automatically creates the public key and private key for us.

The [Interface] is the configuration on your Client and the [Peer] section is the Configuration for the Server, the [Peer] and [Interface] is reversed with the configuration of the server

[Interface] 
PrivateKey = Your client private key 
Address = 10.8.0.2/24 
DNS = 1.1.1.1 
 
[Peer] 
PublicKey = Your server public key 
AllowedIPs = 0.0.0.0/0 
Endpoint = Your server ip and port, for example 1.1.1.1:51820

That’s all for the client. However, in order to make it work, we have to configure the [Peer] section in your Server’s configuration and restart the Wireguard service.

wg0.conf on your Ubuntu instance 
 
[Peer] 
PublicKey = Your client public key (Windows instance in my case)

Now, we can click Activate on the Client and verify your self hosted VPN.