Deploy the blackbox-exporter helm chart on Azure Kubernetes Service (AKS)

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Pulumi · Accepted Answer

To deploy the `blackbox-exporter` Helm chart on Azure Kubernetes Service (AKS), we will perform the following steps:

1. **Create an AKS cluster**: We will use the `KubernetesCluster` class from the `azure` Pulumi package to create an AKS cluster in Azure. The AKS cluster provides the Kubernetes environment where our applications will run.

2. **Install the Helm chart**: After the AKS cluster is up and running, we will use the `Chart` class from the `kubernetes` Pulumi package to deploy the `blackbox-exporter` Helm chart. Helm is a package manager for Kubernetes which allows us to define, install, and upgrade complex Kubernetes applications.

3. **Configuration**: We will need to configure our deployment by specifying the necessary Helm chart values that the `blackbox-exporter` might require.

Below is a Pulumi TypeScript program that accomplishes these tasks. This program assumes you have already set up Pulumi, have an account and an active subscription on Azure, and have the necessary permissions to create resources.

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

// Step 1: Create an AKS cluster
const resourceGroup = new azure.core.ResourceGroup("myResourceGroup", {
    location: "East US", // Choose an appropriate Azure region for your AKS cluster
});

const aksCluster = new azure.containerservice.KubernetesCluster("myAKSCluster", {
    resourceGroupName: resourceGroup.name,
    location: resourceGroup.location,
    defaultNodePool: {
        name: "default",
        nodeCount: 2, // Specify the desired node count for your cluster
        vmSize: "Standard_DS2_v2", // Choose an appropriate VM size
    },
    dnsPrefix: `${pulumi.getStack()}-kube`,
    linuxProfile: {
        adminUsername: "adminuser",
        sshKey: {
            keyData: "ssh-rsa YOUR_SSH_PUBLIC_KEY", // Replace with your SSH public key
        },
    },
    servicePrincipal: {
        clientId: "YOUR_SP_APP_ID", // Replace with your service principal's app ID
        clientSecret: "YOUR_SP_SECRET", // Replace with your service principal's secret
    },
});

// Export the kubeconfig
export const kubeconfig = aksCluster.kubeConfigRaw;

// Step 2: Install the Helm chart for blackbox-exporter
const chart = new kubernetes.helm.v3.Chart("blackbox-exporter", {
    chart: "blackbox-exporter",
    version: "0.7.0", // Specify the chart version you wish to deploy
    fetchOpts: {
        repo: "https://prometheus-community.github.io/helm-charts", // Official Prometheus community Helm charts repository
    },
    namespace: "monitoring", // Deploy this in the 'monitoring' namespace or another namespace of your choice
    values: {
        // Define any necessary values that you want to configure for blackbox-exporter
    },
}, { provider: new kubernetes.Provider("k8s-provider", { kubeconfig: aksCluster.kubeConfigRaw }) });

// Optional: Export the status URL for blackbox-exporter
export const blackboxExporterUrl = pulumi.interpolate`http://blackbox-exporter.monitoring.svc.cluster.local:9115`;

```

**Explanations:**

- We start by importing the necessary Pulumi packages for Azure and Kubernetes.

- We then create a new Azure resource group using `azure.core.ResourceGroup` to manage the resources. The `location` argument determines where the resources will be located geographically.

- Next, we create the AKS cluster by instantiating `azure.containerservice.KubernetesCluster`. This creates a managed Kubernetes cluster on Azure. It includes configuration for the admin user, node size, and service principal. **Note:** The service principal enables AKS to interact with Azure APIs.

- We also export the `kubeconfig` from the AKS cluster, which is needed to interact with the Kubernetes cluster using `kubectl` or Pulumi's Kubernetes provider.

- Then we create an instance of `kubernetes.helm.v3.Chart` to represent the `blackbox-exporter` Helm chart. We pass in the AKS cluster's kubeconfig to the Kubernetes provider, telling Pulumi to deploy the Helm chart to our AKS cluster.

- Optionally, we export the `blackboxExporterUrl`, which is a URL to access the deployed `blackbox-exporter`. This is an internal cluster URL not accessible from outside the AKS cluster without additional ingress setup.

- Replace placeholders like `YOUR_SSH_PUBLIC_KEY`, `YOUR_SP_APP_ID`, and `YOUR_SP_SECRET` with your actual SSH public key and Azure service principal credentials to authenticate with Azure.

Make sure you review and adjust the configuration, like namespace and resource names, to fit your specific needs before running the program. To deploy the resources, run `pulumi up` after saving the above script to a `index.ts` file in a Pulumi project directory.