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SSH into Linux boxes with PowerShell from Windows Server 2016

With an ever-changing IT environment, you need a way to manage everything from a centralized location, if possible. If you're in a Windows/Linux hybrid environment, PowerShell is your friend. Let's get started.

First, you will need a nifty little module called Posh-SSH on your Windows Server/Desktop. You can install this by running;

Install-Module Posh-SSH

 After that, you want to ensure SSH is configured on your Linux box. Depending on what distro, these settings may vary. I personally like using open-SSH. You can check the status of SSH on your Linux box by typing;

sudo service ssh status


After that, we will be good to start an SSH session from our Windows Server/Desktop.

The first thing we want to do is open up PowerShell ISE. We also want to ensure to store this SSH session into a variable. Use the following one-liner;

$Sess = New-SSHSession -ComputerName IPADDRESS -Credential (get-credential)


 When the credentials pop up, you will type in your username and password. (please note: you don't have to do username@hostname or username@ipaddress like you would in traditional SSH).


Next, we want to run Get-SSHSession  to confirm an SSH session has been open. You should see something like the following;


Finally, we are ready to run our command. We will use the Invoke-SSHCommand cmdlet to run our command. In my case, I'm going to use a simple "ls" to list some files.

Invoke-SSHCommand -SSHSession $Sess -Command {ls}

 You should see output like this;


There you have it! You have officially ran SSH from Windows to Linux. I'll leave you with a quick and dirty function/cmdlet that I created to create multiple SSH sessions and the ability to run a command against multiple Linux boxes.


Function New-SSHConnection {
    
    [cmdletbinding(SupportsShouldProcess = $true, ConfirmImpact = 'High')]
    Param (
        [Parameter(ParameterSetName = 'DeviceIP',
            Position = 0,
            ValueFromPipeline,
            ValueFromPipelineByPropertyName)]
        [string[]]$deviceIP,

        [Parameter(ParameterSetName = 'DeviceHostname',
            Position = 0,
            ValueFromPipeline,
            ValueFromPipelineByPropertyName)]
        [string[]]$Hostname,

        [Parameter(Mandatory,
            HelpMessage = 'Please enter a command you would like to run on the device')]
        [string]$Command,

        [Parameter(Mandatory,
            HelpMessage = 'Please enter a username for your device you want to SSH into')]
        [string]$Username

    )
    Begin {
        Add-Type -AssemblyName System;
        Add-Type -AssemblyName System.Management.Automation;

        Import-Module Posh-SSH
        Write-Output "Starting: ($($MyInvocation.MyCommand.Name))"
        $Pass = New-Object System.Management.Automation.PSCredential -ArgumentList  $Username, (Read-Host 'Please enter password' | ConvertTo-SecureString -AsPlainText -Force)
        
        #If DeviceIP is selected, use this array
        $deviceArray = @()
        $deviceArray += $deviceIP

        #If Hostname is selected, use this array
        $deviceArray2 = @()
        $deviceArray2 += $Hostname
    }
    Process {
        if ($PSCmdlet.ShouldProcess($deviceIP -or $PSCmdlet.ShouldProcess($Hostname))) {
            if ($deviceIP) {
                $SSHSession = New-SSHSession -ComputerName $deviceArray -Credential $Pass
            }   

            elseif ($Hostname) {
                $SSHSession = New-SSHSession -ComputerName $deviceArray -Credential $Pass
            }
        }
    
        Foreach ($Device in $SSHSession) {
            $invokeSSHCommandPARAMS = @{
                'SSHSession'       = $Device
                'Command'          = $Command
                'EnsureConnection' = $true
            }
            $invokeSSHCommand = Invoke-SSHCommand @invokeSSHCommandPARAMS
            
            $invokeSSHCommandOBJECT = [pscustomobject] @{
                'IP_or_Host'    = $invokeSSHCommand.Host
                'CommandOutput' = $invokeSSHCommand.Output
            }
            $invokeSSHCommandOBJECT

            Start-sleep -Seconds 7
        }           
    }#Process
    End {Get-SSHSession | Remove-SSHSession}
}#Function

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