Adding Storage for Containerized Applications

9 Adding Storage for Containerized Applications

You can add persistent storage for use by applications on an OKE cluster node. Storage created in a container's root file system will be deleted when you delete the container. For more durable storage for containerized applications, configure persistent volumes to store data outside of containers.

A persistent volume (PV) is storage that enables your data to remain intact when the containers to which the storage is connected are terminated.

A PV is a resource in the cluster. A persistent volume claim (PVC) is a request for a PV resource. A PVC is a storage request that is met by binding the PVC to a PV. A PVC provides an abstraction layer to the underlying storage.

You can provision PVCs using the following methods:

Block volumes. Attach volumes from the Private Cloud Appliance Block Volume service. The volumes are connected to clusters created by OKE using a CSI (Container Storage Interface) volume plugin deployed on the clusters.
- To provision a regular block volume, see Creating Persistent Block Volume Storage.
- To provision a high performance block volume, see Creating Persistent High Performance Block Volume Storage.
For information about block volumes on the Private Cloud Appliance, see the Block Volume Storage Overview chapter in the Oracle Private Cloud Appliance Concepts Guide and the Block Volume Storage chapter in the Oracle Private Cloud Appliance User Guide.
File systems. Mount file systems from the Private Cloud Appliance File Storage service. The File Storage service file systems are mounted inside containers running on clusters created by OKE using a CSI volume plugin deployed on the clusters.
- Provision a PVC on a new file system using the CSI volume plugin. Create a storage class and a PVC. The CSI volume plugin dynamically creates both a new File Storage service file system and a new persistent volume backed by the new file system. See Creating Persistent File System Storage Using the CSI Volume Plugin.
- Provision a PVC on an existing file system. Create a file system, mount target, PV, and PVC. See Creating Persistent File System Storage Using an Existing File System.
For information about file systems on the Private Cloud Appliance, see the File Storage Overview chapter in the Oracle Private Cloud Appliance Concepts Guide and "Creating a File System, Mount Target, and Export" in the File System Storage chapter in the Oracle Private Cloud Appliance User Guide.