The Oracle ZFS Storage Appliance manages physical storage using a pooled storage model where all filesystems and LUNs share common space. This topic describes how storage is organized using storage pools, projects, and shares.
Storage Pools
The appliance is based on the ZFS filesystem, which groups underlying storage devices into pools. Filesystems and LUNs, collectively referred to as shares, allocate from this storage pool as needed. Before creating filesystems or LUNs, you must first configure storage on the appliance. Once a storage pool is configured, there is no need to statically size filesystems, though this behavior can be achieved by using quotas and reservations.
While multiple storage pools are supported, this type of configuration is generally discouraged because it provides significant drawbacks as described in the Configuring Storage section. Multiple pools should only be used where the performance or reliability characteristics of two different profiles are drastically different, such as a mirrored pool for databases and a RAID-Z pool for streaming workloads.
When multiple pools are active on a single host, the BUI displays a drop-down list in the menu bar that can be used to switch between pools. In the CLI, the name of the current pool will be displayed in parenthesis, and can be changed by setting the 'pool' property. If there is only a single pool configured, then these controls will be hidden. When multiple pools are selected, the default pool chosen by the UI is arbitrary, so any scripted operation should be sure to set the pool name explicitly before manipulating any shares.
Projects
All filesystems and LUNs are grouped into projects. A project can be considered a consistency group, that defines a common administrative control point for managing shares. All shares within a project can share common settings, and quotas can be enforced at the project level, as well as the share level. Projects can also be used solely for grouping logically related shares together, so their common attributes (such as accumulated space) can be accessed from a single point.
By default, the appliance creates a single default project when a storage pool is first configured. It is possible to create all shares within this default project, although for reasonably sized environments creating additional projects is strongly recommended, if only for organizational purposes.
Shares
Shares are filesystems and LUNs that are exported over supported data protocols to clients of the appliance. Exported filesystems can be accessed over SMB, NFS, HTTP/WebDav, and FTP. LUNs export block-based volumes and can be accessed over iSCSI or Fibre Channel.
The project/share is a unique identifier for a share within a pool. Projects within a pool cannot contain shares with the same name. If you attempt to name or rename a share using a name that is already in use, a mount point error occurs.
In addition to the default properties, you can configure shares and projects with any number of additional properties. These properties are given basic types for validation purposes, and are inherited like most other standard properties. The values are never consumed by the software in any way, and exist solely for end-user consumption. The property schema is global to the system, across all pools, and is synchronized between cluster peers.
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