If you haven’t done already, take a look at my previous post to use wsltty to view the local WSL installation, which is then used to ssh into a remote box.

For the purpose of this explanation the client is the machine you’re sitting at, and the server is the remote machine you’re connecting to.

First, we need to get SSH X11 Forwarding working. This would normally be used for running graphical applications, but we’re just using it for the clipboard feature.

Server Configuration

You should have these lines uncommented in /etc/ssh/sshd_config

X11Forwarding yes
X11DisplayOffset 10
X11UseLocalhost no

When you’re done restart the ssh daemon, on my (Debian) system the command is this:

sudo systemctl restart ssh

If you’re running a firewall on the server you need to enable loopback. I’m using iptables, so this is how I’d do it:

sudo iptables -I INPUT -i lo -j ACCEPT
sudo iptables -I OUTPUT -o lo -j ACCEPT
su -
iptables-save > /etc/iptables/rules.v4
exit

Client configuration

From within WSL (but not ssh’d into a remote system), Install xauth and xterm:

sudo apt install xauth xterm

A big thanks to this video for help with the next section: youtube.com/watch?v=_MgrjgQqDcE

In Windows, download and install VcXsrv https://sourceforge.net/projects/vcxsrv/

Find XLaunch in the start menu and run it.

On the first screen choose Multiple Windows and set the Display number to 0:

Choose Start no client on the next page:

Make sure Clipboard is turned on

Press Save configuration.

Type shell:startup in the address bar and hit enter – this will take you to a special folder – files saved here will run when a user logs in. The filename should be pre-populated as config.xlaunch. That’s OK so hit Save, and then Finish in the previous window.

Finally, go back to WSL. This command tells your local WSL (the client) where to find the display. SSH uses that information when you link to the remote computer (server).

export DISPLAY=localhost:0

You can also save this line into ~/.bashrc on the client to load it every time WSL starts.

Connect and Test

In WSL, connect to the server with a slightly modified command:

ssh -Y joebloggs@remotelinuxcomputer.example.com

The -Y tells ssh you want to link the server to the VcXsrv software, so the server can display things on the client’s screen.

Let’s test with xeyes

sudo apt install xeyes
xeyes

A pair of eyes should appear on your screen, and follow the mouse around.

Put it to use!

So, what we have now is that anything that goes onto the Linux system clipboard (xclip) should end up on the Windows clipboard too. Lets give it a try. Pipe some data to xclip:

echo "I'm copied, paste me!" | xclip -i

Now try pasting that into a text editor on windows.

Next, copy some text in windows, then go back to your ssh session and type:

xclip -o

The text you copied should appear on a new line in the terminal.

The real power of this comes when combined with terminal applications that are aware of the system clipboard. For me, I wanted to copy from vim in an ssh session, and then paste into windows. If you’re using a version of vim with enough features (I use vim-gtk), all you have to do is add this to your ~/.vimrc:

" Yank goes to system clipboard, to aid with WSL copy/paste
set clipboard=unnamedplus

Now, anything copied by the yank commands ends up in the windows clipboard too.

Here’s how to set it up.

Install Windows Subsystem for Linux (WSL):

1. Open Powershell as an administrator
2. Enter this command:
   Enable-WindowsOptionalFeature -Online -FeatureName Microsoft-Windows-Subsystem-Linux
3. When it’s done, restart your computer.

Install Linux (on WSL)

I recommend Debian – it’s well supported by the community, and a pretty lightweight install compared to some of the other choices.

For the local windows store

1. Open the Windows Store
2. Search for “Debian”
3. Click on Get
4. Click on Install

Once it’s installed:

1. Find and click on the Debian app in your start menu
2. Wait for a moment, then set up a username for this local installation of linux. It’ll be slightly more convenient if you use the same username you have on your remote linux machines.
3. Exit the terminal: type:
   exit
   and press enter.

This info came from https://docs.microsoft.com/en-us/windows/wsl/install-win10

Install WSLtty

1. Go to https://github.com/mintty/wsltty/releases/latest
2. Choose the right release for your system – unless you have a fairly old computer it’ll be the one ending in “x86_64.exe”
3. Download and install.
4. This app isn’t digitally signed in a way approved by Microsoft, so a warning will pop up (“Windows protected your PC”). Click More info then Run anyway.

Run and connect!

Mintty should have installed a shortcut called “WSL Terminal” with the linux penguin icon, click on it and you’ll get a black terminal windows with prompt in the top left: [your unix username]@[computer name]:~$

Let’s get your local linux system up to date:

1. Type sudo apt update then press enter.
2. Type in your local linux password (that you created earlier)
3. sudo apt upgrade, then press y and enter when asked if you want to continue
4. It may take a little while, depending on the speed of your pc and internet connection.
5. Finally lets install ssh:
   sudo apt install ssh

Now we can connect to a remote linux computer:

If the username on the remote computer is the same as the one you created earlier, the command is:
ssh remotelinuxcomputer.example.com or ssh 192.168.2.1, when you put in the computer’s name or ip address.

If the username is different, no problem, do this:
ssh joebloggs@remotelinuxcomputer.example.com
or
ssh joebloggs@192.168.2.1

In either case, you will probably get a warning about “the authenticity of the host xxxxx can’t be established”. Don’t worry, just type yes, then enter you password for the remote computer, and you’re in!

One final tip

If ssh into remote computers is all your do with this, then log out, the login command will be remembered by the shell, even if you reboot.
Next time you open the WSL terminal, press the “Up” as many times as you need to scroll through the command history and find the one you wanted.