PSSession management in PowerShell - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a PSSession in PowerShell?

A PSSession is a persistent connection to a remote computer that allows you to run commands and scripts on that computer as if you were working locally.

beginner

How do you create a new PSSession to a remote computer named 'Server01'?

Use the command: New-PSSession -ComputerName Server01 to create a new session to 'Server01'.

beginner

How can you list all active PSSessions in your current PowerShell session?

Use Get-PSSession to see all active PSSessions you have open.

beginner

What command closes a specific PSSession stored in a variable $session?

Use Remove-PSSession -Session $session to close and remove that session.

intermediate

Why is it useful to use PSSessions instead of running commands directly with Invoke-Command?

PSSessions keep the connection open, so you can run multiple commands efficiently without reconnecting each time. This saves time and resources.

Which command creates a new persistent remote session in PowerShell?

A Remove-PSSession

B New-PSSession

C Get-PSSession

D Invoke-Command

New-PSSession creates a new persistent remote session.

How do you see all your active remote sessions?

A Get-RemoteSession

B Show-PSSession

C Get-PSSession

D List-PSSession

Get-PSSession lists all active PSSessions.

What does Remove-PSSession do?

A Closes and removes a session

B Lists sessions

C Creates a new session

D Runs a command remotely

Remove-PSSession closes and removes a session.

Why use PSSession over Invoke-Command for multiple commands?

A PSSession keeps connection open for efficiency

B PSSession is slower

C Invoke-Command keeps connection open

D No difference

PSSession keeps the connection open, making multiple commands faster.

Which command runs a command inside an existing PSSession stored in $session?

A New-PSSession -Session $session

B Remove-PSSession -Session $session

C Get-PSSession -Session $session

D Invoke-Command -Session $session -ScriptBlock { }

Invoke-Command with -Session runs commands inside an existing session.

Explain how to create, use, and close a PSSession in PowerShell.

Think about the lifecycle of a remote session.

Describe the benefits of using PSSession management for running multiple remote commands.

Consider time and resource savings.

Practice

1. What is the primary purpose of a PSSession in PowerShell?

easy

A. To store variables locally on your computer

B. To create a persistent connection to a remote computer for running commands

C. To display graphical user interfaces

D. To compile PowerShell scripts into executables

Solution

1. Step 1: Understand what PSSession does

   A PSSession creates a persistent connection to a remote computer, allowing you to run commands there without reconnecting each time.

2. Step 2: Compare options to this definition

   Only To create a persistent connection to a remote computer for running commands describes this purpose. Other options describe unrelated tasks.

3. Final Answer:

   To create a persistent connection to a remote computer for running commands -> Option B

4. Quick Check:

   PSSession = persistent remote connection [OK]

Hint: PSSession = persistent remote connection [OK]

Common Mistakes:

• Confusing PSSession with local variable storage
• Thinking PSSession creates GUIs
• Assuming PSSession compiles scripts

2. Which of the following is the correct syntax to create a new PSSession to a computer named 'Server01'?

easy

A. Get-PSSession -ComputerName Server01

B. Invoke-Command -ComputerName Server01

C. New-PSSession -ComputerName Server01

D. Remove-PSSession -ComputerName Server01

Solution

1. Step 1: Identify the cmdlet to create a session

   The cmdlet to create a new session is New-PSSession.

2. Step 2: Check the syntax for specifying the remote computer

   The parameter -ComputerName followed by the computer's name is correct for New-PSSession.

3. Final Answer:

   New-PSSession -ComputerName Server01 -> Option C

4. Quick Check:

   Create session = New-PSSession [OK]

Hint: New-PSSession creates sessions; use -ComputerName for target [OK]

Common Mistakes:

• Using Invoke-Command instead of New-PSSession to create session
• Using Remove-PSSession to create session
• Confusing Get-PSSession with creation

3. What will be the output of this PowerShell code?

 $session = New-PSSession -ComputerName localhost
Invoke-Command -Session $session -ScriptBlock { Get-Process | Select-Object -First 1 }
Remove-PSSession -Session $session 

medium

A. Displays the first process running on the local computer

B. Creates a session but does not display any output

C. Throws an error because Remove-PSSession is called too early

D. Displays all processes running on the local computer

Solution

1. Step 1: Understand the commands

   The code creates a session to localhost, runs a command to get the first process, then removes the session.

2. Step 2: Analyze the Invoke-Command output

   The Invoke-Command runs Get-Process | Select-Object -First 1 remotely, so it outputs the first process object.

3. Final Answer:

   Displays the first process running on the local computer -> Option A

4. Quick Check:

   Invoke-Command outputs first process [OK]

Hint: Invoke-Command outputs scriptblock result before Remove-PSSession [OK]

Common Mistakes:

• Thinking Remove-PSSession stops output
• Assuming no output from Invoke-Command
• Confusing output with all processes

4. You run this script:

 $session = New-PSSession -ComputerName Server01
Invoke-Command -Session $session -ScriptBlock { Get-Date }
Remove-PSSession -Session 

But it throws an error: "Remove-PSSession : Cannot bind argument to parameter 'Session' because it is null." What is the problem?

medium

A. Invoke-Command syntax is incorrect

B. New-PSSession failed to create a session

C. Get-Date cannot run inside a PSSession

D. Remove-PSSession is missing the -Session parameter with the session variable

Solution

1. Step 1: Identify the error cause

   The error says Remove-PSSession has a null argument for -Session, meaning it was called without specifying which session to remove.

2. Step 2: Check the Remove-PSSession command usage

   The script calls Remove-PSSession -Session without the $session value, so PowerShell doesn't know which session to close.

3. Final Answer:

   Remove-PSSession is missing the -Session parameter with the session variable -> Option D

4. Quick Check:

   Remove-PSSession needs -Session argument [OK]

Hint: Always specify -Session when removing sessions [OK]

Common Mistakes:

• Forgetting to pass the session variable to Remove-PSSession
• Assuming Remove-PSSession closes all sessions by default
• Blaming Invoke-Command or New-PSSession incorrectly

5. You want to run a command on multiple remote computers and keep the sessions open for later use. Which approach correctly creates sessions for 'Server01' and 'Server02' and stores them for reuse?

hard

A. $sessions = New-PSSession -ComputerName Server01
$sessions += New-PSSession -ComputerName Server02
Invoke-Command -Session $sessions -ScriptBlock { hostname }

B. $sessions = New-PSSession -ComputerName Server01, Server02
Invoke-Command -ComputerName Server01, Server02 -ScriptBlock { hostname }

C. Invoke-Command -ComputerName Server01, Server02 -ScriptBlock { hostname }
$sessions = $null

D. $sessions = New-PSSession -ComputerName Server01
Invoke-Command -Session $sessions -ScriptBlock { hostname }
Remove-PSSession -Session $sessions

Solution

1. Step 1: Recall how to create persistent sessions for multiple computers

   New-PSSession can take multiple ComputerName values or create separately and collect into an array with +=. Invoke-Command must use -Session $sessions (array) to run on persistent sessions.

2. Step 2: Evaluate each option

   A creates sessions but uses -ComputerName on Invoke-Command, creating temporary connections instead of using persistent ones. B builds the array explicitly and uses -Session. C uses temporary only. D removes sessions.

3. Final Answer:

   $sessions = New-PSSession -ComputerName Server01 $sessions += New-PSSession -ComputerName Server02 Invoke-Command -Session $sessions -ScriptBlock { hostname } -> Option A

4. Quick Check:

   Build session array with +=, use -Session [OK]

Hint: Create and store sessions in a variable array for reuse [OK]

Common Mistakes:

• Removing sessions immediately before reuse
• Not storing sessions in a variable
• Using Invoke-Command without sessions for reuse