Enabling multi-hop Longhorn upgrade

You can enable multi-hop Longhorn upgrades to allow direct Cloudera Embedded Container Service upgrades starting from Cloudera Data Services on premises 1.5.5 SP2 to Cloudera Data Services on premises 1.5.5 SP4, bypassing the intermediate releases.

A new feature flag Enable Longhorn Multi-hop Upgrade is introduced which is disabled by default. When enabled, it separates the Longhorn upgrade into a dedicated step during the upgrade process. A separate Update Longhorn step is added to the upgrade process, which is specific to Cloudera Embedded Container Service service.

You can lookup for this new feature flag in your Cloudera Manager instance under Clusters → [Select your Experience Cluster] → Configuration. And search for the feature flag (longhorn_multihop_enabled).
In Cloudera Manager, navigate to Cloudera on premises and click the icon, then click Update.
On the Getting Started page, you can select the Install method - Air Gapped or Internet and proceed. For more information on the pre-upgrade checklist, see Pre-upgrade checklist.

Internet install method

Air Gapped install method

Click Next.
On the Collect Information page, click Next.
important
If you are using a custom docker repository, you have an option to clear your obsolete Docker images. Note that this is a post-upgrade clean up option available only when you selected the custom docker repository during your installation.
- As part of the upgrade process workflow, this step is the only opportunity for you to generate a post-upgrade cleanup script.
- Must be run only after the successful upgrades of all Cloudera Embedded Container Service clusters using the same custom docker repository.
On the Install Parcels page, click Next.
On the Update Data Services page, you can view the progress of your upgrade. Post Upgrade Validation is run and these are a set of health checks added as the last step in the upgrade to verify that the upgrade was successful and the cluster is healthy. This includes verifying that the services are healthy, the hosts are upgraded to the new version, and that the control plane is in a healthy state after upgrade. For the control plane to be determined as good health, it will verify that RKE2, Longhorn, and Vault are healthy. It will also check that the critical pods in the Cloudera Control Plane namespace are up and running.
Click Next after the upgrade is complete .
On the Update Longhorn page you can view the progress of the Longhorn upgrade.
After the upgrade is complete, the Summary page appears. You can now Launch Cloudera on premises from here.

If you see a Longhorn Health Test message about a degraded Longhorn volume, wait for the cluster repair to complete.

Or you can navigate to the Cloudera Data Services on premises page and click Open Cloudera on premises.

Cloudera Data Services on premises UI displays in a new window.
important
Please revert the changes to the original state for the Session Timeout: (session_timeout) after the upgrade process. And follow the same steps to update the session timout.
caution
During the course of the multi-hop Longhorn upgrade process, if you lose the instance of the Upgrade wizard window, then perform the following steps:
1. From your Cloudera Manager instance → Running Commands and identify the Upgrade Cluster command. Make sure this command ran successfully.
2. After the upgrade process is completed, verify if the Longhorn version is pointing to the latest version by navigating to the storage UI. Under the Longhorn dashboard → Advanced tab → Engine Images and make sure that the latest Longhorn Engine Image is deployed.
3. If the latest Longhorn version is not deployed, then run the multi-hop Longhorn upgrade command using the API.
  You can trigger the API using the following path: /controlPlanes/commands/startLonghornMultihopUpgrade
  Once the API successfully completes, the Longhorn Multihop Upgrade Command starts running and you can track the progress from the Running Commands pane.