linux tunnel from one ip to another code example

Example 1: port forwarding linux

echo 1 | sudo tee /proc/sys/net/ipv4/ip_forward
# ENABLES IP FORWARDING TEMPORARILY

Example 2: port forwarding linux

sudo nano /etc/sysctl.conf
# UNCOMMENT `net.ipv4.ip_forward=1`
#AFTER, EXECUTE THESE COMMANDS
sudo sysctl -p
sudo sysctl --system