Cinder System Architecture¶
The Cinder Block Storage Service is intended to be ran on one or more nodes.
Cinder uses a sql-based central database that is shared by all Cinder services in the system. The amount and depth of the data fits into a sql database quite well. For small deployments this seems like an optimal solution. For larger deployments, and especially if security is a concern, cinder will be moving towards multiple data stores with some kind of aggregation system.
Below you will find a brief explanation of the different components.
DB: sql database for data storage. Used by all components (LINKS NOT SHOWN).
Web Dashboard: potential external component that talks to the api.
api: component that receives http requests, converts commands and communicates with other components via the queue or http.
Auth Manager: component responsible for users/projects/and roles. Can backend to DB or LDAP. This is not a separate binary, but rather a python class that is used by most components in the system.
scheduler: decides which host gets each volume.
volume: manages dynamically attachable block devices.
backup: manages backups of block storage devices.