Upgrade, Rollback and Uninstall

After deploying IBM certified container software for Connect:Direct Web Services, you can perform following actions:
  • Upgrade, when you wish to move to a new release
  • Rollback, when you wish to recover the previous release version in case of failure
  • Uninstall, when you wish to uninstall

Upgrade – Upgrading a Release

To upgrade the chart ensure that the pre-installation tasks requirements are in-place on the cluster (Kubernetes or OpenShift). Following things must be considered while following pre-installation tasks requirement for upgrade:
  1. Since, upgrade takes backup of configuration data on the Persistent Volume. Ensure that you have sufficient space available to accommodate the backup and running IBM Connect:Direct Web Services data. A copy of backup is kept on Persistent Volume to enable rollback in case of upgrade failures.
    Example: The default minimum Persistent Volume size requirement for new deployment is 500Mi. We can just double it for upgrade i.e. 1000Mi.
  2. Re-run the SecurityContextConstraints scripts to ensure that the any new changes are in-place in project on OpenShift cluster.

  3. Check the Connect:Direct Web Services secrets are still valid and available on the cluster.
  4. Depending upon the accessibility of the public internet on the cluster. The upgrade procedure can be Online upgrade and Offline upgrade.

Online upgrade

You have access to the public internet on the cluster. Thus, you have access to Entitled registry and IBM public GitHub repository. Follow these steps to upgrade the chart with release name my-release:
  1. Update the local repo:
    helm repo update
  2. Download the newer helm chart:
    helm pull ibm-helm/ibm-cdws
    The helm chart gets pulled in current directory.
  3. Untar the chart and run the SecurityContextConstraints scripts to ensure any new required change is in-place on the cluster. Refer Creating security context constraints for Red Hat OpenShift Cluster for the cluster.
  4. Upgrade the chart.
    helm upgrade my-release ibm-cdws-1.0.x.tgz --reuse-values -f values.yaml

Offline upgrade

You don't have access to the public internet on the cluster. Thus, Entitled registry and public IBM GitHub registry cannot be accessed from cluster. So, you need to follow the Offline (Airgap) Cluster procedure to get the installation files. Follow these steps to upgrade the chart with release name my-release:
  1. After you have the installation files, go inside the charts directory used for downloading the files.
    cd <download directory>/charts
    Download directory is directory where the installation files have been downloaded.
  2. Untar the chart and run the SecurityContextConstraints scripts to ensure any new required change is in-place on the cluster. Refer Creating security context constraints for Red Hat OpenShift Cluster for the cluster.
  3. Upgrade the chart:
    helm upgrade my-release ibm-cdws-1.0.x.tgz--reuse-values -f values.yaml
    Refer steps mentioned in Validating the Installation for validating the upgrade.
Note: For both online and offline processes:
  • Do not change/update the values of Connect:Direct Web Services configuration parameters.
  • If any new parameters are introduced in the new chart and you are upgrading using new chart. Then, all those new parameters should be either passed with "--set" option or using a yaml file with "-f" option. The parameter can have default values as specified in the new chart or you can change the values as per your configuration requirement.

Rollback – Recovering on Failure

Procedure

  1. To rollback a chart with release name my-release to a previous revision invoke the following command:
    helm rollback my-release <previous revision number>
  2. To get the revision number execute the following command:
    helm history my-release
    Note: The rollback is only supported to a previous release. Subsequent rollbacks are not supported.

Uninstall – Uninstalling a Release

To uninstall/delete a Chart with release name my-release invoke the following command:
helm delete my-release
Note:
This command removes all the Kubernetes components associated with the Chart and deletes the Release. Certain Kubernetes resources created as an installation prerequisite for the Chart and a helm hook ie ConfigMap will not be deleted using the helm delete command. Delete these resources only if they are not required for further deployment of IBM Certified Container Software for Connect:Direct Web Services. If deletion is required, you have to manually delete the following resources:
  • The persistent volume
  • The secret
  • The Config Map