Set Up a WireGuard VPN Server on Linux

WireGuard is a modern, fast VPN that's built into the Linux kernel. It's simpler to configure than OpenVPN and delivers better performance.

Prerequisites

• Ubuntu 22.04+ server with a public IP
• Root access
• A client device (laptop, phone, etc.)

Step 1: Install WireGuard

sudo apt update
sudo apt install wireguard

Step 2: Generate Server Keys

wg genkey | tee /etc/wireguard/server_private.key | wg pubkey > /etc/wireguard/server_public.key
chmod 600 /etc/wireguard/server_private.key

Step 3: Create Server Config

sudo nano /etc/wireguard/wg0.conf

[Interface]
Address = 10.0.0.1/24
ListenPort = 51820
PrivateKey = <server_private_key>
Enable NAT
PostUp = iptables -A FORWARD -i wg0 -j ACCEPT; iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
PostDown = iptables -D FORWARD -i wg0 -j ACCEPT; iptables -t nat -D POSTROUTING -o eth0 -j MASQUERADE
[Peer]
Client 1
PublicKey = <client_public_key>
AllowedIPs = 10.0.0.2/32

Replace eth0 with your server's main network interface.

Step 4: Enable IP Forwarding

echo "net.ipv4.ip_forward = 1" | sudo tee -a /etc/sysctl.conf
sudo sysctl -p

Step 5: Start WireGuard

sudo systemctl enable wg-quick@wg0
sudo systemctl start wg-quick@wg0
sudo wg show

Step 6: Open Firewall Port

sudo ufw allow 51820/udp

Step 7: Generate Client Keys

wg genkey | tee client_private.key | wg pubkey > client_public.key

Step 8: Create Client Config

[Interface]
Address = 10.0.0.2/24
PrivateKey = <client_private_key>
DNS = 1.1.1.1
[Peer]
PublicKey = <server_public_key>
Endpoint = your.server.ip:51820
AllowedIPs = 0.0.0.0/0
PersistentKeepalive = 25

Import this config into the WireGuard app on your device.

Step 9: Add More Clients

For each new client:

1. Generate a new key pair
2. Add a [Peer] block to the server config with the client's public key and a unique IP (10.0.0.3/32, 10.0.0.4/32, etc.)
3. Restart WireGuard: sudo systemctl restart wg-quick@wg0

Troubleshooting

• Can't connect? Check that port 51820/UDP is open on your cloud provider's firewall
• No internet through VPN? Verify IP forwarding and NAT rules
• Check status: sudo wg show shows connected peers and data transfer

Conclusion

You now have a working WireGuard VPN. It's one of the fastest and simplest VPN solutions available. Use it to secure your remote access and protect traffic on untrusted networks.