Getting started with Zero Downtime Upgrade (ZDU)
Understand what ZDU process is and when you can use this process to upgrade your existing Cloudera Runtime Private Cloud Base cluster to the latest version. Also, review the high-level steps involved in completing a Zero Downtime upgrade.
Before you upgrade your Cloudera Runtime cluster using the Zero Downtime Upgrade (ZDU) process, it is a best practice to review the high-level ZDU steps, the software requirements, and the limitations and considerations related to service components.
Before you plan the upgrade, you must be aware of the tasks you must complete to ensure the cluster readiness.
What Zero Downtime Upgrade (ZDU) is
Zero Downtime Upgrades (ZDUs) are an evolution to the legacy method of performing a rolling upgrade on components in a cluster. Zero Downtime Upgrades aim to optimize the upgrade process to allow end-users to continue using major services while upgrading CDP Private Cloud Base cluster. In this initial release, some services will perform a quick restart, greatly reducing the amount of downtime end-users have historically experienced during a cluster upgrade.
After completing the preparatory steps, you use the Cloudera Manager upgrade wizard to complete the upgrade. Cloudera Manager restarts all services after the upgrade. Services that support rolling upgrade are restarted in a rolling fashion, and do not require you to take the services offline during the upgrade. All other services are restarted normally.
When to use ZDU process
- A higher version of Cloudera Runtime
- A maintenance release of Cloudera Runtime
Activities to complete before starting ZDU
- Understand and review the following:
- Perform the following prerequisite tasks:
Zero Downtime Upgrade (ZDU) process
- Review the software requirements before performing the upgrade.
- Review notes and warnings to be aware of the pre upgrade tasks required from your end before performing the upgrade.
- Back up the cluster managed by Cloudera Manager and back up all your components before performing the Zero Downtime Upgrade.
- Back up Cloudera Manager again.
- Access the Parcels required to install Cloudera Runtime.
- Upgrade the parcels.