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7 - SSH Port Forwarding ​

Note: Just a command-line exercise. No terraform needed.

The Problem: You want to access a web server (port 80) on a remote machine, but the firewall only allows SSH (port 22).

The Solution: Use SSH Local Port Forwarding (-L) to tunnel port 80 traffic through your established SSH connection.

Prerequisites ​

  • SSH access to remote host (HostB)
  • Service running on remote host (e.g., nginx on port 80)

Objective ​

Use ssh -L to tunnel remote HTTP to your local machine (http://localhost:2000).

How-to ​

1. Establish the Tunnel ​

Run this on your local machine:

bash
ssh -L localhost:2000:localhost:80 user@HostB

What this does:

  • Listens on local port 2000
  • Forwards traffic through the SSH tunnel to HostB
  • Sends it to localhost:80 (relative to HostB)

2. Access the Service ​

Open your local browser to: http://localhost:2000

You're now viewing the remote web server, bypassing the firewall.