OpenStack is a cloud computing software developed by NASA and Rackspace, which is licensed by Apache License and is a free software and open source project. OpenStack is the IaaS (infrastructure, service) software that allows anyone to build and provide cloud computing services on their own. In addition, OpenStack is also used to create a "private cloud" within a firewall (private Cloud) that provides the resources shared by organizations or departments within the enterprise.
The cinder provides a OpenStack block service. Similar to Amazon's EBS block storage service, instances in OpenStack are unsustainable and need to be mounted volume to implement persistence in volume. Cinder is to provide the implementation management function of the storage block unit that the volume actually needs. This project is separated from the Nova. Its predecessor was Nova-volume. Although the Nova became more complex, and the block service was so important, in the Folsom version, Cinder was separated from the Nova. Storage vendors are very active because they can be combined with commercial storage.
The following illustration is the internal architecture of the OpenStack:
The following figure is the cinder schema: