Deploy the linkerd helm chart on Opensshift

Question

Pulumi · Accepted Answer

To deploy the Linkerd Helm chart on an OpenShift cluster using Pulumi, we'll use the Pulumi Kubernetes provider. This provider allows us to define a Helm chart deployment as part of our infrastructure as code.

The following Pulumi TypeScript program demonstrates how to deploy the Linkerd Helm chart to an existing OpenShift cluster. Before applying this Pulumi code, make sure you have configured `kubectl` to connect to your OpenShift cluster and have the necessary permissions to deploy resources.

Here's a step-by-step explanation of how the code works:

1. **Import Necessary Libraries**: We import Pulumi's Kubernetes library to interact with the Kubernetes API and deploy the Helm chart.
2. **Create a Chart Resource**: We create an instance of `Chart` from `@pulumi/kubernetes/helm/v3` to deploy Linkerd.
3. **Set Chart Parameters**: We specify the chart name (`linkerd2`), the repository where the chart can be found, and the namespace for the deployment.
4. **Run Deployment**: A `pulumi up` command will deploy Linkerd as defined by the Helm chart to the connected OpenShift cluster.

Now, let's look at the actual Pulumi program:

```typescript
import * as k8s from "@pulumi/kubernetes";

// Define the Linkerd Helm chart from the official repository.
const linkerdChart = new k8s.helm.v3.Chart("linkerd", {
    chart: "linkerd2",
    version: "2.9.4", // Specify the version of Linkerd chart you wish to deploy.
    fetchOpts: {
        repo: "https://helm.linkerd.io/stable",
    },
    namespace: "linkerd",  // The namespace in which to deploy Linkerd, this namespace will be created if it doesn't exist.
});

// Export the Linkerd web dashboard URL by constructing it using cluster information.
export const linkerdDashboardUrl = pulumi.interpolate`http://localhost:8084`; // Assuming port-forwarding is set up for the Linkerd web dashboard.

```

To deploy this chart, you would run `pulumi up` in the terminal in the directory where this code is saved. The `pulumi up` command examines the desired state defined in your code and attempts to achieve that state in your OpenShift cluster.

After the deployment is complete, and in case you've set up port-forwarding as mentioned in the export statement (via `kubectl port-forward` or other means), you can access the Linkerd Dashboard via `http://localhost:8084`.

Before running the program, please make sure you have installed Pulumi and set up the Kubernetes configuration for your Openshift cluster. You need appropriate access rights to deploy resources to the cluster. The version of the Linkerd Helm chart is set to `2.9.4` in this example, which you can change to the version you want to deploy.

This code assumes that you are running it with an already authenticated `kubectl` that has the context of your OpenShift cluster set as the current context. If you need to target a specific cluster context, you can set the `kubeconfig` field in the `Chart` resource options.