Automated VM Patch Management with Azure Automation

Question

Pulumi · Accepted Answer

Automated VM Patch Management with Azure Automation involves leveraging Azure services to automate the deployment of updates to virtual machines (VMs) in your environment. Pulumi provides an infrastructure as code approach to define and manage your Azure resources, including those needed for automated patch management.

For automated VM patch management, you will typically need an Azure Automation Account which acts as a centralized hub for managing automation across your Azure and non-Azure environments. Within this account, you would use Update Management, a feature that lets you manage operating system updates for your Windows and Linux computers.

To represent the automated patch management scenario using Pulumi, we'll create several resources:

1. `Automation Account`: Acts as the central hub for your automation tasks.
2. `Schedule`: Defines the frequency and timing of the patching process.
3. `Software Update Configuration`: Specifies which VMs to update, the schedule of updates, and the pre/post scripts if necessary.
4. `Hybrid Runbook Worker Group`: If you have VMs outside of Azure that you want to manage, you will use a Hybrid Runbook Worker. This allows on-premises machines to interact with Azure Automation.

Let's define the Pulumi program in Python to set up these resources:

```python
import pulumi
import pulumi_azure as azure

# Create a resource group for the automation account
resource_group = azure.core.ResourceGroup('rg', name='patch-management-rg')

# Create an automation account where all automation components will reside
automation_account = azure.automation.Account('automationAccount',
    name='patch-management-automation-account',
    location=resource_group.location,
    resource_group_name=resource_group.name,
    # The SKU name should be one of Basic or Free
    # Here we use Basic for continuous delivery without interruptions.
    sku_name='Basic',
)

# Create a schedule for the automation to run (e.g., daily at 03:00 AM UTC)
schedule = azure.automation.Schedule('schedule',
    name='daily-patch-schedule',
    resource_group_name=resource_group.name,
    automation_account_name=automation_account.name,
    # Define the frequency of the schedule (OneTime, Daily, Hourly, Weekly, Monthly)
    frequency='Daily',
    # Starting daily at the following UTC time (format 'hh:mm')
    timezone='UTC',
    start_time='03:00',
)

# Configure the software update configuration associating the VM(s) to the patching schedule
# Note: The code below assumes that you already have an Azure VM or VMSS resource created.
# Please replace 'your-vm-name' with the appropriate resource identifiers for targeting.
# This is not a complete implementation of software update configuration due to its complexity.
# For a full implementation, the use of Azure Automation SDK or a custom script might be needed.
update_configuration = azure.automation.SoftwareUpdateConfiguration('updateConfig',
    name='vm-patch-configuration',
    resource_group_name=resource_group.name,
    automation_account_name=automation_account.name,
    # Schedule details
    schedule_info=schedule.id,
    # Target VMs for the update configuration
    targets={
        'azure_vm_resource_ids': [
            '<your_vm_resource_id_here>',
        ],
        # Alternatively, use Azure Tags to include VMs in Update Management
        'non_azure_query': {
            # Details here would be specific to your Non-Azure environment configuration
        },
    },
    # Define patch inclusion/exclusion as per requirements
    update_configuration={
        'operating_system': 'Windows',  # Or use 'Linux'
        # More properties can be defined for detailed configuration
    },
    # Optional: pre/post scripts, included/excluded patches, maintenance settings, etc.
)

# (Optional) If managing non-Azure VMs, you'll set up a Hybrid Runbook Worker Group
# Note that you'll need to complete additional steps not covered here such as
# installing and registering the Hybrid Runbook Worker on the non-Azure VM(s).
hybrid_worker_group = azure.automation.HybridRunbookWorkerGroup('hybridWorkerGroup',
    name='external-vm-patch-group',
    resource_group_name=resource_group.name,
    automation_account_name=automation_account.name,
    # Relevant properties including credential, worker registration info, etc.
)

# Export the Automation Account name and the Schedule name
pulumi.export('automation_account_name', automation_account.name)
pulumi.export('schedule_name', schedule.name)
```

In this Pulumi program, we've set up the core components needed to automate patch management for Azure VMs:

- A new automation account is established in the resource group `patch-management-rg`.
- A daily schedule is created for when patching should occur.
- We defined an update configuration, although this is a placeholder for the actual implementation, which often requires a deeper integration with Azure APIs or SDKs.

This example is an outline that demonstrates the kind of resources needed for VM patch management with Azure Automation. For actual deployment, each resource would require additional properties to be set according to your specific environment and needs. You can refer to the Pulumi [Azure Automation documentation](https://www.pulumi.com/docs/reference/pkg/azure/automation/) for detailed information on each resource and available settings.