Initiating diagnostic operations on Azure VMs via Run Command

Question

Pulumi · Accepted Answer

To initiate diagnostic operations on Azure Virtual Machines (VMs) using Pulumi with the Azure provider, you'll need to use the `VirtualMachineRunCommandByVirtualMachine` resource from the `azure-native` package. This resource allows you to execute a script or a set of commands on an existing Azure VM.

The `VirtualMachineRunCommandByVirtualMachine` resource is specifically designed for running commands directly on Azure VMs. You can provide a script or command to execute, which can include diagnostic operations. For automated diagnostics, your command or script would typically include the necessary instructions to collect and log system information, performance metrics, or any other required diagnostics data.

Here's how you could structure the Pulumi program in TypeScript to execute a diagnostic operation:

1. Install the necessary Pulumi Azure plugin.
2. Import the `azure-native` package in your program.
3. Use the `VirtualMachineRunCommandByVirtualMachine` resource, specifying the `resourceGroupName`, `location`, `vmName`, and details of the script or commands to run.

Below is a detailed Pulumi TypeScript program that demonstrates how to initiate diagnostic operations on a specific Azure VM:

```typescript
import * as azure from "@pulumi/azure-native";

// Define the Azure resource group and VM where you wish to perform diagnostics.
const resourceGroupName = "my-resource-group";
const vmName = "my-vm";
const location = "West US"; // Change it to the location of your VM

// Provide the command and script content that you want to run on the VM for diagnostics.
// It can be a single command or a script block.
// Here, as an example, we're using a shell command to check system disk usage.
const commandToExecute = "df -h";

// Create the Run Command instance to run the command on the VM.
const runCommand = new azure.compute.VirtualMachineRunCommandByVirtualMachine(`${vmName}-RunCommand`, {
    // Specify the name, resource group, and location of the VM.
    vmName: vmName,
    location: location,
    resourceGroupName: resourceGroupName,
    // Define the source with the script to be executed. The commandId should match the platform (`RunShellScript` for Linux or `RunPowerShellScript` for Windows).
    source: {
        script: commandToExecute, // You can also use `script` instead of `commandId` to run a custom script
        commandId: "RunShellScript" // Or "RunPowerShellScript" if it's a Windows VM.
    },
    // Optionally, provide authentication details, define a timeout for the command, and add parameters if your script requires them.
});

// Export the id of the run command to access or track the operation outside Pulumi.
export const runCommandId = runCommand.id;
```

In this program:

- We import the `azure-native` package, which provides all the bindings to create Azure resources.
- We define constants for the resource group name, VM name, and location, which need to match the VM you are targeting for diagnostics.
- We prepare a command (`commandToExecute`) that will run on the target VM. You can modify this command or script content to fit your diagnostic operations.
- We create the `VirtualMachineRunCommandByVirtualMachine` resource, setting up the `location` and `resourceGroupName` along with the script or command payload that we want to execute.
- We use the `commandId` property to reference predefined scripts; in this case, "RunShellScript" signifies that we're running a shell script on a Linux VM. For Windows VMs, use "RunPowerShellScript".
- We export the `runCommandId` which can be used to later reference this specific invocation, for instance, to check the status or fetch the logs.

Make sure you adjust the `commandToExecute` and other parameters to fit the specific diagnostic operation you want to perform on your Azure VM.

After writing this code, run it using the Pulumi CLI to deploy your changes and execute the run command on the VM.

Remember to replace placeholder values (e.g., `my-resource-group`, `my-vm`, and the script content) with actual information from your Azure environment.