Wireguard on Google Cloud

Server side

Install wireguard client

sudo apt update
sudo apt install wireguard
sudo apt install ufw
sudo apt install iptables

Generate private/pulic key

Private key

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

Public key

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

Create Wireguard config file

sudo nano /etc/wireguard/wg0.conf

add tihs inside

[Interface]
Address = 192.168.10.1/24
DNS = 8.8.8.8
DNS = 1.1.1.1
SaveConfig = true
ListenPort = 51820
PrivateKey = <SERVER_PRIVATE_KEY>
PostUp = iptables -A FORWARD -i %i -j ACCEPT; iptables -t nat -A POSTROUTING -o <SERVER_INTERFACE> -j MASQUERADE
PostDown = iptables -D FORWARD -i %i -j ACCEPT; iptables -t nat -D POSTROUTING -o <SERVER_INTERFACE> -j MASQUERADE


[Peer]
PublicKey = <CLIENT_PUBLIC_KEY>
AllowedIPs = 192.168.10.5/32 # Client ip

Setup ip forwarding

sudo nano /etc/sysctl.conf

Edit this line

net.ipv4.ip_forward=1

See the result

sudo sysctl -p

Setup firewall

sudo ufw allow 51820/udp
sudo ufw allow 22/tcp
sudo ufw enable
sudo ip link set dev wg0 mtu 1360