libvirt: StorPool Volume Attachment

There are various Cinder volume drivers providing access to network-attached storage, such as GlusterFS, NFS, RBD, etc. The purpose of this blueprint is to add a driver supporting the volumes defined in a StorPool cluster.

StorPool is distributed data storage software running on standard x86 servers. StorPool aggregates the performance and capacity of all drives into a shared pool of storage distributed among the servers. Within this storage pool the user creates thin-provisioned volumes that are exposed to the clients as block devices. StorPool consists of two parts wrapped in one package - a server and a client. The StorPool server allows a hypervisor to act as a storage node, while the StorPool client allows a hypervisor node to access the storage pool and act as a compute node. In OpenStack terms the StorPool solution allows each hypervisor node to be both a storage and a compute node simultaneously.

The proposed driver will make use of the StorPool API (based on JSON over HTTP) to query, manage and attach volumes defined in the StorPool cluster. It will include all the features required by the Kilo release.

Since the test setup requires an operational StorPool cluster, the unit tests will mostly use mocking to simulate the operations. A separate continuous integration environment will be set up by StorPool and access to it will be provided for running automated CI tests.