CDP Public Cloud upgrade advisor
Compute resources deployed via cloud services are generally considered transient in nature. With the separation of compute and storage, compute clusters in CDP can be stopped or decommissioned, while the data used or created by workloads running on these clusters generally remains accessible on persistent cloud storage.
There are some exceptions to the above, most importantly SDX metadata and cloud service-specific metadata. SDX metadata is stored in the Data Lake, while metadata specific to a cloud service may be stored in databases, local configurations, or even locally attached disks. This local storage can also be persistent (block storage volumes) or transient (ephemeral disks).
In cloud services where compute is elastic and state is transient, we need safeguards to protect all data that is not persistent, especially when changes are performed on the services themselves. In CDP Public Cloud, there can be several changes, most notably Runtime maintenance upgrades, Runtime minor/major software version upgrades, and OS upgrades.
In general, there are two main approaches to upgrading cloud services:
- Backup, re-create and restore
- In-place upgrade
These two approaches have similarities: a prior backup should be performed, service endpoints should remain stable after the operation, and they should result in the same outcome. CDP Public Cloud supports both approaches. While the first approach may be convenient for simple data workloads, complex data applications and their custom data pipelines spanning multiple clusters may require an in-place upgrade path.
In this guide we will describe the high-level steps of performing in-place upgrade of Data Lake and Data Hub clusters. For steps required for the backup and restore approach, refer to the respective documentation on backing up Data Lakes and Data Hubs and performing metadata restore (automated for Data Lake clusters only).