This is a fork of github.com/kubernetes-incubator/external-storage, which is no longer maintained. Latest code lives in https://github.com/libopenstorage/external-storage/tree/openstorage-5.5.
This repository houses community-maintained external provisioners plus a helper library for building them. Each provisioner is contained in its own directory so for information on how to use one, enter its directory and read its documentation. The library is contained in the lib directory.
An external provisioner is a dynamic PV provisioner whose code lives out-of-tree/external to Kubernetes. Unlike in-tree dynamic provisioners that run as part of the Kubernetes controller manager, external ones can be deployed & updated independently.
External provisioners work just like in-tree dynamic PV provisioners. A StorageClass object can specify an external provisioner instance to be its provisioner like it can in-tree provisioners. The instance will then watch for PersistentVolumeClaims that ask for the StorageClass and automatically create PersistentVolumes for them. For more information on how dynamic provisioning works, see the docs or this blog post.