Introduction

The Cinder block storage service provides block storage volumes as a service. Cinder allows creating block-device volumes and attaches them to Nova virtual machine instances. Cinder supports multiple vendors backend drivers which allows utilizing various storage devices, such as local logical volume management (LVM), NetApp, EMC storage arrays, and others. Cinder accesses the storage device via its management access and lets a Nova virtual machine instance access volumes directly via the storage path. The storage path depends on the implementation of the storage array and could be an iSCSI target, fiber channel, or other.

It is important to note that Cinder is not a shared storage solution such as a storage area network (SAN) that allows attaching a volume to multiple servers. Cinder allows attaching a volume to only one instance at a time.

Native cloud applications are stateless by nature; thus, the Nova virtual machine instance does not save any data on the ephemeral disk...