Deploy an Example Application with Argo CD

Prerequisites

Before applying Argo CD with SmoothGlue Enterprise, ensure you have the following:

• SmoothGlue Enterprise deployed on a system

• Access to the web interface of Argo CD

• Credentials for logging into Argo CD

• Namespace setup with correct labels

• Iron Bank Credentials loaded on the cluster

Once all prerequisites are met, an application can be deployed via Argo CD.

Namespace Labeling Requirements

In order for the Podinfo application to be deployed in SmoothGlue Enterprise, a namespace with the following labels is required:

• istio-injection=enabled

The Istio label ensures that the Istio sidecar is injected and the application is integrated into the service mesh.

• zarf.dev/agent=ignore

The Zarf agent label disables the mutating webhook and allows the workload to pull images from external sources to the cluster.

Creating a namespace and labeling it (if using an existing namespace skip the creation step):

kubectl create namespace applications
kubectl label namespace applications istio-injection=enabled zarf.dev/agent=ignore

Iron Bank Credentials

By default, SmoothGlue is configured to pull Iron Bank containers from Zarf's registry. However, if that has been disabled via configuration it is required to pull from Iron Bank in order for Istio's pods to be deployed (since the namespace ignores the local Zarf registry).

The following command will create a secret that will pull images from Iron Bank:

kubectl create secret docker-registry private-registry --docker-server=registry1.dso.mil --docker-username=<your-username> --docker-password=<your-password> -n application

Deploying Podinfo with Argo CD

In this example, we will set up Argo CD to Sync and deploy Podinfo to the Kubernetes cluster. Upon logging into Argo CD, select Create Application.

1. Set the Application Name to podinfo.

2. Set the Project to the default setting.

3. Leave the Sync Policy set to Manual.

4. In the source section, add the following to the Repository URL: https://github.com/stefanprodan/podinfo.

5. Set the Path to Kustomize.

6. Under Destination, set the Cluster URL to: https://kubernetes.default.svc.

7. Set the Namespace to applications.

8. Under the Kustomize section, set the image to: registry.dso.mil/runyontr/podinfo.

9. Set the Version to: 5.1.4.

10. On the top right of Argo CD open the Edit by Yaml. Add the label zarf.dev/agent: ignore to the metadata.

It should look like this.

apiVersion: argoproj.io/v1alpha1
kind: Application
metadata:
  name: podinfo
  labels:
    zarf.dev/agent: ignore
spec:
  destination:
    namespace: applications
    server: https://kubernetes.default.svc
  source:
    kustomize:
      images:
      - ghcr.io/stefanprodan/podinfo=registry.dso.mil/runyontr/podinfo:5.4.1
    path: kustomize
    repoURL: https://github.com/stefanprodan/podinfo
    targetRevision: HEAD
  project: default

note

The label zarf.dev/agent: ignore will prevent Zarf from mutating the Repo URL.

11. Click Create.

12. Select the app in the list of applications and click Sync.

13. In the side window, click Synchronize.

The application will synchronize and deploy Podinfo to the cluster. Once it has been fully deployed, it will report back with a healthy icon in Argo CD.

In order to access the application, a VirtualService must be created to access it via the browser. The following file enables access to Podinfo via the browser. Replace EC2-Host with the same IP as the other VirtualServices.

apiVersion: networking.istio.io/v1beta1
kind: VirtualService
metadata:
  name: podinfo-virtual-service
  namespace: applications
spec:
  gateways:
    - istio-system/public
  hosts:
    - podinfo.<EC2-Host>.nip.io
  http:
   - route:
      - destination:
          host: podinfo
          port:
            number: 9898

Once the file is on the system, it needs to be applied to the cluster with the following command:

kubectl apply -f <VirtualServiceFile>.yaml

Now that the VirtualService has been created, you can access it via: https://podinfo<EC2-Host>.nip.io.