OpenShift and StorageOS communicate with each other to perform actions such as creation, deletion and mounting of volumes. The standard communication procedure in OpenShift versions 3.x uses REST API calls. However, StorageOS also implements communication using CSI. When using CSI, OpenShift and StorageOS communicate via a Linux socket. This socket is created and handled by the Kubelet on the host.
OpenShift v4 uses CSI by default.
CSI (Container Storage Interface) Note
CSI is the standard that enables storage drivers to release on their own schedule. This allows storage vendors to upgrade, update, and enhance their drivers without the need to update Kubernetes source code, or follow Kubernetes release cycles.
CSI is in “Technology Preview and not for production workloads” in OpenShift 3.11. StorageOS recommends the use of CSI for OpenShift v4, as CSI is generally available in Openshift v4
The user can provide standard PVC definitions and StorageOS will dynamically provision them. StorageOS presents volumes to containers with standard POSIX mount targets. This enables the Kubelet to mount StorageOS volumes using standard linux device files. Checkout device presentation for more details.
StorageOS supports OpenShift 3.9, 3.10, 3.11, 4.1, 4.2 and 4.3.
To install StorageOS on OpenShift, please follow our installation instructions page.