Upgrading Ozone overview
You must understand the overview of the upgrade feature. By upgrading the CDP Runtime parcels using Cloudera Manager, Ozone is also upgraded. This Ozone upgrade provides you with new features that are made available with the 7.1.9 release.
This feature helps you upgrade or downgrade Ozone. Ozone upgrade from Cloudera Manager is managed by upgrading the CDP parcels. Before upgrading the CDP parcels, as a pre-upgrade step, you must take a backup of OM metadata and SCM metadata. Ozone will be brought to a read-only state before the upgrade and this helps the OMs to synchronize before the upgrade. The upgrade is completely managed by Cloudera Manager.
When the new version of Ozone starts, new features are not yet available. This allows you to downgrade to an older version. In case you wish to downgrade, then the older version of Ozone is restored. However, data written in the newer version is still readable by the older version of Ozone.
If you wish to finalize the upgrade and enable the new features, you must run the Finalize Upgrade command. This updates the metadata layout of Ozone services, persists the changes required for the new version, and enables the new features.