Sample repository for Kubernetes Instana agent version pinning

This repository serves as an example how to control Instana agent updates by pinning of the agent versions in Kubernetes environments by using ArgoCD by utilizing the environment variables. For more information check the official documentation on configuring updates.

Pinning of the agent in operator and helm chart installation

1. Verify kubectx points to the right cluster

2. kubectl installed

3. Verify ArgoCD is installed in the cluster

   kubectl get pods -n argocd
   

   If it's not installed, follow the instructions at https://argo-cd.readthedocs.io/en/stable/getting_started/.

4. Construct the instana-agent.customresource.yaml for the operator installation, example or values.yaml for the helm-chart installation, example. The available environment variables for configuring the updates are INSTANA_AGENT_UPDATES_TIME, INSTANA_AGENT_UPDATES_FREQUENCY, and INSTANA_AGENT_UPDATES_VERSION. For the available agent, check https://github.com/instana/agent-updates/tags. See Agent Configuration documentation for more information about these settings.

   Once you create the file with desired configuration, commit and push the changes to the remote repository.

5. Ensure that the GitHub repo is either a public repository or that Argo CD has appropriate access to pull from it. Access can be configured using a GitHub access token or the SSH key authentication. First, create a secret in the cluster. For the GitHub access token, run:

   kubectl create secret generic git-credentials --from-literal=username=<git-username> --from-literal=password=<git-token> -n argocd
   

   For the SSH key authentication, first generate the key. Once the SSH key is generated, determine the path of the private key (~/.ssh/id_rsa by default), and add the key to the Github repository settings. Then, create the git-credentials secret:

   kubectl create secret generic git-credentials \
       --from-file=sshPrivateKey=<path-to-your-ssh-private-key> \
       -n argocd
   

   Then, follow the steps to add the Git repo to ArgoCD:

   kubectl port-forward svc/argocd-server -n argocd 8080:443
   

   argocd login localhost:8080
   

   When promted to enter the credentials for logging in, enter admin for the username. To get the password, run:

   kubectl get secret argocd-initial-admin-secret -n argocd -o jsonpath="{.data.password}" | base64 --decode
   

   Once logged in, add the GitHub repo with argocd command. If you are using the GitHub access token, run:

   argocd repo add <github-repo-url> \
    --username <git-username> --password <git-password>
   

   Alternatively, if you are using the SSH authentication, run:

   argocd repo add [email protected]:<your-org/your-repo>.git \
    --ssh-private-key-path <private-key-path> \
    --name <your-repo-name>
   

6. Create an Argo CD Application manifest that instructs ArgoCD to monitor and apply any changes from the GitHub repository to the cluster. For the example for the operator CR, please check the operator example and for the helm chart installation, please chec the values.yaml example).

   • use spec.target.revision to specify which branch should be applied to the cluster. It's possible to have a branch per environment, e.g. test, stage and prod, so that each Instana agent version is tested out before using it in production.

7. If running the operator installation, run the following command. Otherwise, skip this step. Deploy the operator. For example, for the manual installation, run:

   kubectl apply -f https://github.com/instana/instana-agent-operator/releases/latest/download/instana-agent-operator.yaml
   

8. Apply the Argo CD Application manifest to the cluster. This is a manual one-time step.

   kubectl apply -f argo-application.yaml -n argocd
   
   

9. Verify that everything is configured properly by updating a pinned version in CR or values.yaml and pushing it to the remote repository. Argo CD should automatically detect changes and sync them to the cluster.