To autostart on boot:

Setting up a VPN on Ubuntu can be done in several ways, depending on whether you want to connect to a VPN service (like NordVPN, ProtonVPN, etc.) or host your own VPN server (using OpenVPN, WireGuard, etc.). Below are the common methods:

Connecting to a VPN Service (e.g., NordVPN, ProtonVPN)

Most commercial VPN providers offer Linux CLI tools or manual setup guides.

Example: NordVPN on Ubuntu

1. Install NordVPN (official method):

   sudo apt update
   sudo apt install nordvpn

2. Log in and connect:

   nordvpn login
   nordvpn connect

Example: ProtonVPN (Official CLI)

1. Install ProtonVPN:

   sudo apt install openvpn dialog python3-pip
   sudo pip3 install protonvpn-cli

2. Initialize and connect:

   sudo protonvpn init
   sudo protonvpn connect

Manual OpenVPN Setup (for .ovpn files)

If your VPN provider supplies .ovpn configuration files:

1. Install OpenVPN:

   sudo apt update
   sudo apt install openvpn

2. Place the .ovpn file in /etc/openvpn/:

   sudo cp your_config.ovpn /etc/openvpn/

3. Start the VPN:

   sudo systemctl start openvpn@your_config

   (Replace your_config with the filename without the .ovpn extension.)

Setting Up WireGuard (Fast & Modern VPN)

WireGuard is lightweight and secure. Many providers (e.g., Mullvad) support it.

Install WireGuard

sudo apt update
sudo apt install wireguard resolvconf

Generate Keys

umask 077
wg genkey | tee privatekey | wg pubkey > publickey

Configure WireGuard

Edit /etc/wireguard/wg0.conf (example client config):

[Interface]
PrivateKey = <your_private_key>
Address = 10.0.0.2/24
DNS = 1.1.1.1
[Peer]
PublicKey = <server_public_key>
Endpoint = vpn.example.com:51820
AllowedIPs = 0.0.0.0/0

Start WireGuard

sudo wg-quick up wg0sudo systemctl enable wg-quick@wg0

Using GNOME's Built-in VPN Support (GUI)

1. Go to Settings > Network > VPN.
2. Click Add VPN and select your protocol (OpenVPN, WireGuard, etc.).
3. Enter your VPN provider's details (server, username, password, etc.).
4. Toggle the VPN to connect.

Troubleshooting

• Permissions Issue: Run VPN commands with sudo if needed.
• DNS Leaks: Use dig +short myip.opendns.com @resolver1.opendns.com to check your IP.
• Kill Switch: Some providers (e.g., NordVPN) offer a kill switch to block traffic if the VPN disconnects.

Summary

• For commercial VPNs: Use the provider's official CLI tool (e.g., nordvpn, protonvpn-cli).
• For OpenVPN: Use sudo openvpn /path/to/config.ovpn.
• For WireGuard: Configure /etc/wireguard/wg0.conf and use wg-quick.
• GUI Method: Use Ubuntu's Network Settings for easy setup.

Let me know if you need help with a specific VPN setup!