SSH port forwarding code example

Example 1: port forwarding linux

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

Example 2: ssh mysql port forwarding

ssh -N -f -L 3336:127.0.0.1:3306 [USER]@[SERVER_IP]

The options used are as follows:

-N - Tells SSH not to execute a remote command.
-L 3336:127.0.0.1:3306 - Creates a local port forwarding. The local port (3306), the destination IP (127.0.0.1) and the remote port (3306) are separated with a colon (:).
[USER]@[SERVER_IP] - The remote SSH user and server IP address.

To run the command in the background, use the -f option.
If the SSH server is listening on a port other than 22 (the default) specify the port with the -p [PORT_NUMBER] option.

Example 3: how to enable the port mapping to the SSH port windos

ssh -R remote_port:localhost:local_port ssh_server_hostname

Example 4: ssh tunnel port

ssh -L 80:intra.example.com:80 gw.example.com