## Mounting a Folder through a firewall using SSH tunneling

Quite often it happens that you want to access a station located behind a firewall and use the file and documents that you have stored there. Particularly, if you are a grad student, you want to connect to your university computer, edit your code, or do whatever that you are doing from a remote location, most possibly from your home.

One method is to just ssh to the firewall and from there ssh to your system and enable the X11 forwarding on both of the ssh connection, using -Y or -X. Then you can launch the editor of your choice, or the program that you need to execute and start working remotely. However, depending on how busy the firewall is, and how good your Internet connection is, you might experience different performance and quality. Quite often it is horrible performance.

You can also use different applications such as VNC or Remote Desktop connections. But these all have a big major problem; most of the time, they are blocked on the firewall. One good alternative is using the TeamViewer. It is easy to install, easy to use, and did I mentioned it is also free! (click here.) But again, the performance you get depends on the network connection and your bandwidth.

The better solution is to mount the remote folder as one of your folders and use the editor on your own computer to edit the file. The only time that you need to pass data over the network is when you need to save the file or read the files.

Previously, I mentioned how to do this on MAC systems using MacFusion, (click here). But if you are outside the university perimeter, you are blocked by the firewall and you are not able to mount the require remote folder locally. Here, it is discussed how to use SSH and SSHFS to accomplish this task.

First you need to have ssh installed. Fortunately it is already installed on MAC and most of the Linux systems. Then you need to install SSHFS. On MAC type “sudo port install sshfs” and on Ubuntu Linux type “sudo apt-get install sshfs”. you are ready.

Now you need to make a tunnel between your machine and the end station passing through the firewall. Just type:

ssh -f UserName@FireWall -L PortNumber:EndStation:22 -N

choose a port number that is not being used on your system. You can check the already used one by typing “netstat”.

You will be asked for your password on the firewall. After the tunneling has been established you need to type

 sshfs -p PortNumber username@127.0.0.1:RemoteLocation LocalMountPoint

remember to use the same PortNumber as the one used in the previous command. RemoteLocation is the folder on the end station that you want to mount, eg. /home/username, and the LocalMountPoint is the address of the local folder that you want it to be mounted to your end station.

Now, the remote location is mounted on your system as if it was one of the folder on your own system. Just execute what ever program that you want and point it to use the files in that folder.

enjoy.

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### 2 Responses to Mounting a Folder through a firewall using SSH tunneling

1. Eduardo says:

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2. Similarly, if you want to actually show code, you can as well:

#include <iostream>


Hope you fin them useful!

• mabouali says:

Nice one. They are certainly useful. Thanks for sharing.