Helm 3 has become the go-to tool for managing Kubernetes applications, but like any tool, it can occasionally run into situations where deployments get stuck or upgrades are pending. This can lead to frustrating delays, especially in environments where rapid deployment and continuous delivery are critical. In this blog, we’ll explore effective techniques to unblock a Helm 3 release that is stuck in an upgrade or deployment process.

Common Causes of Stuck Deployments in Helm 3

Before diving into the solutions, it’s useful to know the typical reasons behind Helm 3 deployments getting stuck:

  1. Failed Release Rollback: A failed upgrade or deployment can leave a release in a pending state while Helm waits for the rollback to complete.
  2. Resource Conflicts: Resource conflicts within Kubernetes, such as locked resources or dependencies, can cause Helm to be unable to complete the deployment.
  3. Secrets and Configurations: Helm stores release information in Kubernetes secrets, and stale or locked secrets can prevent Helm from continuing with the upgrade or deployment.

Let’s explore how to tackle these issues and unblock a Helm 3 release. 
 

1. Deleting Stuck Helm Release Secrets

Helm stores release metadata in Kubernetes secrets, which can sometimes get stuck or become locked during deployments or upgrades. Deleting the stuck secrets can often resolve issues and allow Helm to move forward with the release.

Steps to delete stuck secrets:

  • Identify the stuck release: List all Helm releases in your namespace:

    helm list --namespace <your-namespace>

  • Delete the release secrets: Each Helm release is stored in a secret that follows the naming convention: sh.helm.release.v1.<release-name>.v<version-number>.

    Delete the specific secret for the release:

    kubectl delete secret sh.helm.release.v1.<release-name>.v<version-number> -n <your-namespace>

  • Force an upgrade: After deleting the secrets, you can force an upgrade or reinstall of the release:

    helm upgrade --install <release-name> <chart-name> --namespace <your-namespace>


2.  Rolling Back a Failed Upgrade

In some cases, a Helm 3 upgrade can get stuck in a pending state due to a failure. You can manually trigger a rollback to the previous version to resolve this.

Steps to rollback:

  • Check the release status:

    helm status <release-name> --namespace <your-namespace>

  • Rollback to the previous release version:

    helm rollback <release-name> <revision-number> --namespace <your-namespace>

  • Monitor the status: Ensure the rollback was successful and check the status again:

    helm status <release-name> --namespace <your-namespace>


3. Identifying and Resolving Resource Conflicts

Helm 3 releases can become stuck if there are resource conflicts in your Kubernetes cluster. This can happen when required resources (such as pods, services, or ingress) are locked, pending, or unable to be scheduled. Such conflicts often occur when there are issues with resource dependencies or when the cluster is experiencing resource pressure (e.g., CPU, memory).

Steps to resolve resource conflicts:

  • Check for pending or unscheduled pods:

    kubectl get pods -n <your-namespace> | grep Pending

    If there are pending pods, it could indicate that the resources are not being allocated properly. You may need to resolve any resource shortages or scheduling issues in the cluster.

  • Verify the resource status of the deployment:

    kubectl describe deployment <release-name> -n <your-namespace>

    Look for any errors or warnings in the deployment description that might explain why the resources are stuck.

  • Check for resource conflicts between releases:

    Sometimes, Helm upgrades or rollbacks can conflict with other releases. To check if other deployments are blocking your Helm release, use:

    kubectl get pods -n <your-namespace> -o wide

    Check if any of the pods are using the same resources or dependencies as your release.

  • Resolve conflicts and reattempt the upgrade:

    Once resource conflicts are identified and resolved, retry the Helm upgrade or install:

    helm upgrade --install <release-name> <chart-name> --namespace <your-namespace>

  • Check Kubernetes events:

    To get a deeper understanding of why resources may be conflicting, review Kubernetes events:

    kubectl get events -n <your-namespace> --sort-by=.lastTimestamp

    This will display events sorted by their most recent timestamp, helping you identify any issues in the cluste


4. Waiting for Resources to Be Ready

Sometimes, Helm 3 deployments get stuck simply because Kubernetes resources, like pods or services, are not ready within the expected time. If a deployment is waiting for a pod to be scheduled or a container to start, the Helm release will be stuck in a pending state.

Steps to wait for resources:

  • Check the status of pods:

    kubectl get pods -n <your-namespace>

    This will show the status of all pods in your namespace. Look for pods in a “Pending” or “CrashLoopBackOff” state.

  • Describe the pod to diagnose issues:

    If a pod is stuck in a “Pending” state, describe the pod to get more information on why it hasn’t been scheduled:

    kubectl describe pod <pod-name> -n <your-namespace>

    Look for resource allocation errors, node pressure, or other issues preventing the pod from being scheduled.

  • Check for dependencies or readiness probes:

    Some deployments may have dependencies, or the application itself may require a readiness probe to confirm it is running properly. If readiness probes are misconfigured, the pod might remain in a pending state.

    If dependencies are missing, update your Helm chart or values file to ensure that necessary resources (like services or persistent volumes) are correctly defined and available.

5. Using helm uninstall for Stuck Releases

In certain cases, a Helm release may remain in a pending state because of persistent issues, even after you’ve attempted to delete stuck secrets, resolve resource conflicts, and ensure resources are ready. In such cases, uninstalling the release and reinstalling it may be the best approach.

Steps to uninstall and reinstall a release:

  • Uninstall the stuck release:

    helm uninstall <release-name> --namespace <your-namespace>

    This command will remove the release from your cluster, including all associated resources like deployments, services, and config maps.

  • Reinstall the release:

    Once the stuck release has been uninstalled, you can reinstall it using the helm install command:

    helm install <release-name> <chart-name> --namespace <your-namespace>

    Ensure that the installation goes smoothly and that there are no conflicts with existing resources in the cluster.

 

6. Verifying Cluster Health and Resource Availability

Another common cause of stuck Helm releases is insufficient resources in the Kubernetes cluster. If the cluster is under heavy load, Helm may not be able to allocate the required resources for the release.

Steps to verify cluster health:

  • Check the status of your nodes:

    kubectl get nodes

    Ensure that all nodes are ready and that there are no resource constraints or failures.

  • Verify the resource usage:

    If there are resource pressure issues (e.g., CPU or memory), you may need to scale your Kubernetes cluster or increase the resource limits for specific pods or services.

    kubectl top nodes kubectl top pods -n <your-namespace>

    If you notice high resource usage, consider scaling your cluster or adjusting resource requests and limits.

     

Managing Helm 3 releases effectively is crucial for maintaining smooth operations in your Kubernetes environments. While encountering stuck deployments or pending upgrades can be a challenge, knowing the common causes and having a clear set of actionable solutions at hand can save you time and frustration. By following the troubleshooting steps outlined in this blog, you can resolve most Helm 3 issues and ensure your applications are deployed and upgraded successfully.

Remember, Kubernetes and Helm are powerful tools, but they require careful monitoring and management to ensure your deployments continue to run seamlessly. By staying proactive with resource allocation, release management, and using best practices, you can minimize the chances of encountering issues in the future.

With these strategies in your toolkit, you’ll be better equipped to handle any Helm 3 deployment challenges that come your way. Happy Helm-ing!