Understanding PowerShell SSH: Best PowerShell 101

In this article, we delve into the world of PowerShell SSH, exploring its capabilities and highlighting the benefits it brings to remote administration and automation tasks. We’ll also explore how PowerShell SSH can streamline repetitive tasks, enhance productivity, and simplify remote management scenarios.

How to get the SSH Client?

To set up an SSH client on Windows 10 using PowerShell, you can follow these steps:

  • First, ensure that the OpenSSH client is installed on your Windows 10 system. Open PowerShell and run the following command:
Get-WindowsCapability -Online | Where-Object {$_.Name -like 'OpenSSH.Client*'}
How to get the SSH Client?
  • If you don’t see any output, it means the OpenSSH client is not installed, and you need to install it.
  • To install the OpenSSH client, run the following command in an elevated PowerShell session:
 Add-WindowsCapability -Online -Name OpenSSH.Client~~~~
How to get the SSH Client?
  • This command installs the OpenSSH client package on your system.
  • To enable and start the SSH Agent service, run the following command:
Start-Service ssh-agent
How to get the SSH Client?
  • To verify that the SSH client is installed correctly, run the following command: ssh -V If the installation was successful, you should see the SSH client version information.
  • By default, the SSH client uses your user account credentials. If you need to configure additional settings, such as using a different SSH key or specifying a different port, you can modify the SSH client configuration file located at %USERPROFILE%\.ssh\config.

Adding the OpenSSH Folder to PATH environment

To add the OpenSSH folder to the PATH environment variable in Windows, you can follow these steps:

  • Open the Start menu and search for “Environment Variables”. Click on “Edit the system environment variables” to open the System Properties window.
  • In the System Properties window, click on the “Environment Variables” button at the bottom.
  • In the Environment Variables window, under the “System variables” section, scroll down and find the “Path” variable. Select it and click on the “Edit” button.
  • In the Edit Environment Variable window, click on the “New” button to add a new entry.
  • Enter the path to the OpenSSH folder in the “New Variable Value” field. By default, the OpenSSH folder is located at C:\Windows\System32\OpenSSH. If you have installed OpenSSH in a different location, specify the appropriate path.
  • Click on the “OK” button to save the changes.
  • Close all the windows by clicking on the “OK” or “Apply” buttons until you are back to the desktop.

After adding the OpenSSH folder to the PATH environment variable, you can use the SSH client and other OpenSSH tools from any location in PowerShell or the command prompt without specifying the full path. Make sure to open a new PowerShell session or command prompt window for the changes to take effect.

PowerShell SSH Subsystem Specification

To specify the SSH subsystem in PowerShell, you can follow these steps:

  • Open a PowerShell session.
  • Use the following command to set the SSH_DEFAULT_SHELL environment variable:
$env:SSH_DEFAULT_SHELL = "SubsystemName"
PowerShell SSH Subsystem Specification
  • Replace "SubsystemName" with the desired SSH subsystem. For example, if you want to use the default subsystem, you can set it to “powershell”.
  • Verify the changes by running the following command:
PowerShell SSH Subsystem Specification

It should display the subsystem name you specified.

By specifying the SSH subsystem, you can control which shell or program is used when connecting to an SSH server using PowerShell. Different subsystems provide different functionality and capabilities. The default subsystem is typically the standard PowerShell shell.

Remember to open a new PowerShell session for the changes to take effect.

Why are PowerShell Comment Blocks Important in Understanding PowerShell SSH?

PowerShell comment blocks explained: In the realm of PowerShell SSH, comment blocks play a critical role in understanding the code. These blocks allow developers to add explanatory comments, making the code more readable and easier to comprehend. Whether it’s documenting specific commands, providing context, or clarifying the purpose of functions, PowerShell comment blocks are invaluable in enhancing the clarity and maintainability of PowerShell scripts.

Linking PowerShell & SSH

To connect to an SSH server using PowerShell, you can utilize the ssh command-line tool or the ssh module available in PowerShell 7 and later versions. Here’s how you can establish an SSH connection:

Using the ssh command-line tool:

  • Open a PowerShell session.
  • Use the following command to initiate an SSH connection:
ssh user@hostname
Linking PowerShell & SSH
  • Replace user with your username and hostname with the hostname or IP address of the SSH server.
  • If it’s your first time connecting to the server, you may be prompted to verify the server’s fingerprint. Confirm the fingerprint to proceed.
  • Enter your password when prompted to authenticate yourself.

Using the ssh module in PowerShell 7 and later:

  • Open a PowerShell 7 or later session.
  • Import the ssh module:
Import-Module OpenSSHUtils
Linking PowerShell & SSH
  • Establish an SSH connection using the New-SshSession cmdlet:
$session = New-SshSession -ComputerName hostname -Credential (Get-Credential) 
Linking PowerShell & SSH
Invoke-SshCommand -SessionId $session.SessionId -Command "your-command"
Linking PowerShell & SSH
  • Replace "your-command" with the desired SSH command.

Remember to replace user and hostname with the appropriate values for your SSH server. SSH connections require the correct username, password, and server information to establish a successful connection. Happy Browsing!