Primary Storage

A primary storage is a storage server used to store disk files, such as root volumes, data volumes, root volume snapshots, data volume snapshots, and image caches, for VM instances.

As shown in Primary Storage.
Figure 1. Primary Storage


A primary storage can either be a local storage or a shared storage.
  • Local Storage: Use the hard disks of a host to store disk files.
  • Network Shared Storage: Support NFS, Shared Mount Point, Ceph, and Shared Block.
    • NFS is a network file system storage.
    • Shared Mount Point supports network shared storages provided by commonly used distributed file systems such as MooseFS, GlusterFS, OCFS2, and GFS2.
    • Ceph uses distributed block storages.
    • Shared Block uses shared block storages.