Although OpenStack is purposely open it partly relies on proprietary storage products. To build your cloud upon a truly open software-defined storage platform (SDS), the storage project openATTIC might be worth a try. openATTIC is a cloud storage platform based on 100% open source. It is optimized for OpenStack's Cinder component and for openQRM.
The openATTIC project has been initiated to support organizations in getting the best return on investment in their data center operations while achieving greatest flexibility. openATTIC is based on open source software and extended with intelligent storage functions. Building software-defined storage platforms with openATTIC is easy as it gives you complete access to all its functionalities via a single central API making integration and extension both simple and inexpensive. openATTIC is hardware-independent and includes intelligent SDS functions such as
- consistent snapshots of VMs, databases and applications
- high availability and high performance
- the comprehensive variety of protocols typical of a unified storage system.
- variety of standard hardware can be used
- secure & enterprise-class reliable
More about the openATTIC project at http://openattic.org/en