Learning Objectives

# Disconnect
Disconnect-VIServer -Server * -Confirm:$false

  • Automate common VM lifecycle actions such as power on, power off, and restart.
  • Create and manage VM snapshots through scripts.
  • Build reusable Python-driven PowerCLI automation for these tasks.
  • Visualize the process with a step-by-step diagram.

My Personal Repository on GitHub

Replace <vcenter-address>, <username>, <password>, and <your-vm-name> as needed.

Prerequisites

  • Completed Articles 1–3 (PowerCLI and Python are installed, and you have scripts working).
  • vCenter or ESXi access with permission to modify VMs and create snapshots.
  • Windows system with PowerCLI.

1. Introduction to VM Lifecycle Automation

# Restart VM
Restart-VMGuest -VM $vmName -Confirm:$false | Out-File -FilePath C:Templifecycle_log.txt -Append

2. PowerShell Script: Power On, Power Off, Restart, and Snapshot VMs

Here is the Python code to execute the above PowerShell script and print the output:

  • Connect to vCenter
  • Power on, power off, and restart a VM
  • Take a snapshot of a VM
  • Log results to a file

# Power on VM
Start-VM -VM $vmName -Confirm:$false | Out-File -FilePath C:Templifecycle_log.txt -Append

Below is a PowerShell script that demonstrates how to:Save as vm_lifecycle.ps1:import subprocessprint("Script Output:", completed_process.stdout)
if completed_process.stderr:
print("Errors:", completed_process.stderr)
You can schedule or trigger this script from other Python programs as needed.# Import PowerCLI
Import-Module VMware.PowerCLIcompleted_process = subprocess.run([
"powershell.exe",
"-ExecutionPolicy", "Bypass",
"-File", ps_script
], capture_output=True, text=True)

Managing VMs at scale is much easier when you automate frequent actions like starting, stopping, restarting, and snapshotting. PowerCLI makes these tasks scriptable, while Python lets you orchestrate and schedule them as part of broader automation workflows.

3. Calling the Lifecycle Script from Python

You have learned how to automate VM lifecycle management and snapshotting using PowerCLI and Python.
These scripts enable faster recovery, testing, and bulk management for your vSphere environment.

Next up: In Article 5, you will learn how to export and visualize your VM inventory and script outputs using Python for reporting and analytics.VMware Repository on GitHub# Set your VM name
$vmName = "<your-vm-name>"

# Power off VM
Stop-VM -VM $vmName -Confirm:$false | Out-File -FilePath C:Templifecycle_log.txt -Append

4. Diagram: VM Lifecycle Automation Flow

5. Best Practices and Safety Tips

  • Snapshot Management:
    Do not keep snapshots for long periods. Regularly remove old snapshots to avoid storage and performance issues.
  • Permissions:
    Scripts that modify VM states should be run only by trusted admins.
  • Testing:
    Always test scripts in a lab before using in production.
  • Logging:
    Use log files to keep a history of automated actions for auditing and troubleshooting.

6. Further Reading

7. Conclusion and Next Steps

By the end of this article, you will:

# Take snapshot
New-Snapshot -VM $vmName -Name “AutoSnapshot_$(Get-Date -Format ‘yyyyMMdd_HHmmss’)” -Description “Automated snapshot via script” | Out-File -FilePath C:Templifecycle_log.txt -Append

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