StorPool volume driver

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.

Prerequisites

• The controller and all the compute nodes must have access to the StorPool API service.

• All nodes where StorPool-backed volumes will be attached must have access to the StorPool data network and run the storpool_block service.

• If StorPool-backed Cinder volumes need to be created directly from Glance images, then the node running the cinder-volume service must also have access to the StorPool data network and run the storpool_block service.

• All nodes that need to access the StorPool API (the compute nodes and the node running the cinder-volume service) must have the following packages installed:

  • storpool-config (part of the StorPool installation)

  • the storpool Python bindings package

  • the storpool.spopenstack Python helper package

Configuring the StorPool volume driver

A valid /etc/storpool.conf file is required; please contact the StorPool support team for assistance.

The StorPool Cinder volume driver has two configuration options that may be specified both in the global configuration (e.g. in a cinder.conf volume backend definition) and per volume type:

• storpool_template: specifies the StorPool template (replication, placement, etc. specifications defined once and used for multiple volumes and snapshots) to use for the Cinder volume type or, if specified globally, as a default value for Cinder volumes. There is no default value for this option, see storpool_replication.

• storpool_replication: if storpool_template is not set, the volume will be created with the specified chain replication and with the default placement constraints for the StorPool cluster. The default value for the chain replication is 3.

Using the StorPool volume driver

The most common use for the Cinder StorPool volume driver is probably attaching volumes to Nova instances. For this to work, the nova-compute service and the os-brick library must recognize the “storpool” volume attachment driver; please contact the StorPool support team for more information.

Currently there is no StorPool driver for Nova ephemeral volumes; to run Nova instances with a StorPool-backed volume as a root device, create a Cinder volume with the root filesystem image, make a snapshot, and let Nova create the instance with a root device as a new volume created from that snapshot.