Managing a Helm Release

4 Managing a Helm Release

Learn how to manage your Helm releases in Oracle Communications Billing and Revenue Management (BRM) cloud native.

Topics in this document:

About Helm Releases

After you install a Helm chart, Kubernetes manages all of its objects and deployments. All pods created through oc-cn-helm-chart and oc-cn-ece-helm-chart are wrapped in a Kubernetes controller, which creates and manages the pods and performs health checks. For example, if a node fails, a controller can automatically replace a pod by scheduling an identical replacement on a different node.

As part of maintaining a Helm release, administrators can check a release's status or revision, update a release, or roll back the release to a previous revision.

Tracking a Release's Status

When you install a Helm chart, it creates a release. A release contains Kubernetes objects, such as ConfigMaps, Secrets, deployments, and pods. Only some objects are up and running immediately. Some objects have a start delay, but the Helm install command completes immediately.

To track the status of a release and its Kubernetes objects, run this command:

helm status ReleaseName -n Namespace

where:

ReleaseName is the name you assigned to this installation instance.
NameSpace is the namespace in which the BRM Kubernetes objects reside.

Updating a Helm Release

To update any override-values.yaml key value after creating a release, run the following command. This command updates or re-creates the impacted Kubernetes objects without impacting other objects in the release. It also makes a new revision of the release.

Note:

Before updating the release, you can check for issues by running the helm upgrade command and appending the --dry-run parameter.

helm upgrade ReleaseName Chart --values OverrideValuesFile --values NewOverrideValuesFile -n Namespace

where:

ReleaseName is the name you assigned to this installation instance.
Chart is the name and location of the chart: oc-cn-helm-chart for BRM cloud native services, oc-cn-ece-helm-chart for ECE cloud native services, or oc-cn-init-db-helm-chart for initializing the BRM database schema.
OverrideValuesFile is the path to the YAML file that overrides the default configurations in the values.yaml file.
NewOverrideValuesFile is the path to the YAML file that has updated values. The values in this file are newer than those defined in values.yaml and OverrideValuesFile.
Namespace is the namespace in which the BRM Kubernetes objects reside.

Checking a Release's Revision

Helm keeps track of the revisions you make to a release. To check the revision for a particular release, run this command:

helm history ReleaseName -n Namespace

where:

ReleaseName is the name you assigned to this installation instance.
Namespace is the namespace in which the BRM Kubernetes objects reside.

Rolling Back a Release To a Previous Revision

To roll back a release to any previous revision, run this command:

helm rollback ReleaseName RevisionNumber -n Namespace

where:

ReleaseName is the name you assigned to this installation instance.
RevisionNumber is the value from the Helm history command.
Namespace is the namespace in which the BRM Kubernetes objects reside.