OKD is capable of provisioning persistent volumes (PVs) using the Container Storage Interface (CSI) driver for IBM® Virtual Private Cloud (VPC) Block Storage.
Familiarity with persistent storage and configuring CSI volumes is recommended when working with a CSI Operator and driver.
To create CSI-provisioned PVs that mount to IBM® VPC Block storage assets, OKD installs the IBM® VPC Block CSI Driver Operator and the IBM® VPC Block CSI driver by default in the openshift-cluster-csi-drivers
namespace.
The IBM® VPC Block CSI Driver Operator provides three storage classes named ibmc-vpc-block-10iops-tier
(default), ibmc-vpc-block-5iops-tier
, and ibmc-vpc-block-custom
for different tiers that you can use to create persistent volume claims (PVCs). The IBM® VPC Block CSI Driver Operator supports dynamic volume provisioning by allowing storage volumes to be created on demand, eliminating the need for cluster administrators to pre-provision storage. You can disable this default storage class if desired (see Managing the default storage class).
The IBM® VPC Block CSI driver enables you to create and mount IBM® VPC Block PVs.
Storage vendors have traditionally provided storage drivers as part of Kubernetes. With the implementation of the Container Storage Interface (CSI), third-party providers can instead deliver storage plugins using a standard interface without ever having to change the core Kubernetes code.
CSI Operators give OKD users storage options, such as volume snapshots, that are not possible with in-tree volume plugins.