Back up your Cluster's Applications and Persistent Volumes
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Back up and restore your cluster’s applications before attempting converting your DKP Essential cluster into a DKP Enterprise Managed cluster in the scope of Platform Expansion: Convert a DKP Essential Cluster to a DKP Enterprise Managed Cluster.
The instructions differ depending on the infrastructure provider of your DKP Essential cluster.
For AWS, refer to: Back up an AWS Cluster
For Azure, vSphere, GCP and pre-provisioned environments, refer to: Back up an Azure, vSphere, GCP or Pre-provisioned Cluster