Container Storage Interface (CSI) is an initiative to unify the storage interface of Container Orchestrator (CO) systems like Kubernetes, Mesos, Docker, Cloud Foundry, etc. combined with a storage vendors like Ceph, Portworx, NetApp, etc.
This means, implementing a single CSI for a storage vendor is guaranteed to work with all COs.
Parts of a CSI Driver
- Controller
- Node
- Identity
Communication between these parts is done via gRPC.
CSI Sanity - a tool to test CSI drivers, that your driver implements correctly all the required methods.
Startup(Identity) -> Create (Controller) -> Use (Node) -> Stop (Node) -> Cleanup (Controller)
- Startup = what's your driver name, what you can do; are you still alive?
- Create = create a volume; attach the volume to the node;
- Use = partition, format, mount the volume; bind mount to the requested container path;
- Stop = unbind; pvc is updated and available for other pods;
- Cleanup = detach the volume from the node; delete the volume;
All methods are idempotent.