How to Use Cyberduck with SFTP over Proxy

If you need to access a remote server through an SFTP connection, but your company's firewall only allows outgoing connections via a proxy, there is a solution that combines the power of SSH and SFTP. This technique uses the `ssh` command with the `-L` option to create a tunnel from your local machine to the target server, and then uses Cyberduck as an SFTP client to connect to the target server through this tunnel.

To set up this connection, you will need to have SSH access to another computer on the same network as the target server. This intermediary machine should be accessible directly, and you will use it as a gateway to reach the target server.

Once you have established an SSH connection to the intermediary machine, you can create an SSH tunnel from your local machine to the target machine using the following command:

```

ssh -L 4040:target_machine_IP:22 intermediary_server_IP

```

This command creates a tunnel on your local machine that listens for incoming connections on port 4040. The traffic is then forwarded through the intermediary machine, which connects to the target machine on port 22.

Next, you need to set up Cyberduck as an SFTP client using this tunnel as a proxy. In Cyberduck, go to the 'Preferences' menu and select the 'SFTP' tab. Under the 'Advanced' section, select 'Custom' for the 'Proxy' option and enter the following settings:

* Protocol: SOCKS

* Host: localhost

* Port: 4040

Now, when you try to connect to the target machine using Cyberduck's SFTP protocol, it will use the SSH tunnel as a proxy to establish the connection. You should then be able to log in and access the target machine just like you would if you were connected directly.

Using this technique, you can bypass corporate firewalls and access remote servers through SFTP connections, all while keeping your traffic encrypted using SSH tunnels.

Cyberduck sftp using proxy