Logic Flow for PowerShell Core in Linux

Learning Objectives

Successfully complete this lab by achieving the following learning objectives:

Perform a System Update, Register the MS RedHat Repository, and Install PowerShell

1. Use the yum command to sync the package index files from their sources via the Internet.

   sudo yum check-update

2. Use the yum command to install the newest versions of all installed packages on CentOS.

   sudo yum update

3. Register the Microsoft RedHat repository.

   curl https://packages.microsoft.com/config/rhel/7/prod.repo | sudo tee /etc/yum.repos.d/microsoft.repo

4. Install PowerShell.

   sudo yum install -y powershell

5. Start PowerShell.

   pwsh

Work with PowerShell Conditional Statements

1. Set variable a equal to 3.

   $a=3

2. Create a new file name script1.ps1 using vi.

3. Input the following into the script1.ps1 file:

   if ($a -gt 2) {
   Write-Host "The value $a is greater than 2."
   }

4. Save the script1.ps1 file in vi using :wq.

5. Run the script1.ps1 file.

   ./script1.ps1

6. Set the variable a equal to 1.

   $a=1

7. Run script1.ps1 again.

   ./script1.ps1

8. Create a new script using vi called script2.ps1.

9. Input the following into the script2.ps1 file:

   if ($a -gt 2) {
   Write-Host "The value $a is greater than 2."
   }
   else {
   Write-Host ("The value $a is less than or equal to 2,")
   }

10. Run the script2.ps1 file.

    ./script2.ps1

11. Change the variable a back to 3.

    $a=3

12. Run the script2.ps1 file again.

    ./script2.ps1

Work with PowerShell Switches to Handle Multiple If Statements

1. Enter the following at the PowerShell prompt:

   switch (3)
   {
   1 {"It is one."}
   2 {"It is two."}
   3 {"It is three."}
   4 {"It is four."}
   }

2. Enter the following at the PowerShell prompt:

   switch (3)
   {
   1 {"It is one."}
   2 {"It is two."}
   3 {"It is three."}
   4 {"It is four."}
   3 {"Three again."}
   }

3. Enter the following at the PowerShell prompt:

   switch (3)
   {
   1 {"It is one."}
   2 {"It is two."}
   3 {"It is three."; Break}
   4 {"It is four."}
   3 {"Three again."}
   }

4. Enter the following at the PowerShell prompt:

   switch (4, 2)
   {
   1 {"It is one." }
   2 {"It is two." }
   3 {"It is three." }
   4 {"It is four." }
   3 {"Three again."}
   }

5. Enter the following at the PowerShell prompt:

   switch (4, 2)
   {
   1 {"It is one."; Break}
   2 {"It is two." ; Break }
   3 {"It is three." ; Break }
   4 {"It is four." ; Break }
   3 {"Three again."}
   }

6. Exit PowerShell.

   exit