Search <book_title>...

NetBackup™ Snapshot Manager for Data Center Administrator's Guide

Last Published: 2025-08-12

Product(s): NetBackup (11.0.0.1)

Terminology

The following table describes the concepts and terms in D-NAS data protection.

Table: D-NAS terminology

Term	Definition
Backup	The process of creating a copy of user data and creating backup images of the data. Can be any of the two: The process of creating a new backup image of the client's data that is tar-formatted. The process of creating a snapshot of the client's data.
Backup host	The backup host acts as a proxy client where the snapshot of the NAS share is staged for reading purpose. All the backup and restore operations are run through the backup host. You can configure NetBackup media servers, clients, or a primary server as a backup host. The backup host is also used as a destination client during restores.
Backup job	A backup job in D-NAS is a compound job. The backup job runs a discovery job for getting information of the data to be backed up. Child jobs are created for each backup host that performs the actual data transfer. After the backup is complete, any temporary files or transient information is cleaned up and then job is marked complete.
Child job	For backup, a separate child job is created for each backup host to transfer data to the storage media.
Copy	An instance of a NetBackup image which can be standalone; it can be read or deleted without affecting any other copy.
Data mover	The mechanism that is used to copy data from storage on the production client to back up storage. Or, to duplicate, the data mover copies data from backup storage to different backup storage. Traditionally, NetBackup functions as the data mover and data travels through clients and media servers. Storage devices can provide more efficient mechanisms to move the data, such as NDMP, built-in replication, or OST (as in Optimized Duplication).
Discovery of NAS shares	When a storage array plug-in is created, a discovery task starts on the Snapshot Manager for Data Center host. The discovery job communicates with the arrays and gathers information of storage array clusters, arrays, volumes, and shares. The discovery runs periodically every 4 hours in a day to refresh its asset information. NetBackup presents this asset information for user selection.
Disk array	A disk array which exposes storage or network shares to a host server over SAN, NAS, NFS, CIFS, or iSCSI protocols.
Dynamic streaming	NetBackup Dynamic streaming is a framework that engages multiple backup and restore streams to read data in a distributed manner and send them for backup storage or the restore location.
Media server	Media servers provide additional storage by allowing NetBackup to use the storage devices that are attached to them. Media servers can also increase performance by distributing the network load. Media servers can also be referred to by using the following terms: Device hosts, when tape devices are present. Storage servers, when I/O is directly to disk. Data movers, when data is sent to independent, external disk devices like OpenStorage appliances.
MSDP	Media Server Deduplication Storage Pool is a NetBackup deduplication technology engine to optimize backup storage.
NetBackup Accelerator	A backup technology that speeds up the backup process by reducing the amount of data sent to the media server. It can be used for full and incremental backups.
NetBackup certificate	A security certificate that is issued from the NetBackup CA.
NetBackup Replication	The process of copying and transferring backups created in one NetBackup domain to the storage of another NetBackup domain. This process creates a duplicate set of backups at a different location. Replication is typically used for disaster recovery purposes. This function is primarily known as Auto Image Replication (AIR) within NetBackup.
NetBackup Snapshot Manager for Data Center	Undertakes on-premises storage array snapshot management and replication tasks. NetBackup Snapshot Manager for Data Center has plug-ins which integrate with REST APIs and SDK of storage array vendors for interaction with storage arrays. NetBackup also enables NetBackup Snapshot Manager for Data Center for snapshot management of Cloud offerings of Storage arrays, viz., NetApp CVO, and Azure Files.
Primary copy	The Primary copy or Copy 1 refers to the snapshot copy of the D-NAS backup job. The backup copies created from the primary snapshot copy are called Copy 2 or secondary copies.
Primary server	The primary server manages backups, archives, and restores. The primary server is responsible for media and device selection for NetBackup. Typically, the primary server contains the NetBackup catalog. The catalog contains the internal databases that contain information about NetBackup backups and configuration.
Primary volume	A unit of storage space that a disk array exposes to a host in the form of a network share (NFS or CIFS) or LUN block device. Primary volumes store an application's active data.
RBAC	Role-based access control. The role administrator can delegate or limit access to the NetBackup UI through the roles that are configured in RBAC.
Role	For RBAC, defines the operations that a user can perform and the NAS shares that they can access. For example, you can configure a role to manage recovery of specific NAS shares and the credentials that are needed for backups and restores. 'Default NAS Administrator' is an RBAC role tailored for NAS administrators.
Replication job	A replication operation is specified in an SLP that was added to a D-NAS policy. Generates a replication parent-child job in the Activity monitor.
Snapshot	Refers to a point-in-time copy of the NAS volume or share on the storage arrays. An image copy that is a snapshot is also considered a replica. A snapshot copy consists of one or more snapshot fragments.
Snapshot job	A NetBackup job that creates a hardware snapshot for the NAS volume or share specified in the policy. NetBackup creates a parent-child job hierarchy, where each child job represents a NAS volume or share in the backup selection.
Storage lifecycle policy (SLP)	NetBackup uses SLPs to manage the lifecycle of a backup or snapshot image. An SLP controls image migration, duplication, and replication within a single NetBackup primary server domain.
Storage server	A storage device that is configured in NetBackup. A storage server is a NetBackup component that represents a disk array.
Storage unit	A storage unit is configured for one of two types of data: Backup storage units contain backup images. A backup storage unit cannot contain snapshots. Snapshot storage units contain snapshots. A snapshot storage unit cannot contain backups. The replication process uses snapshot storage units in snapshot replication configurations.
Vendor Change Tracking (VCT)	Several NAS storage array vendors feature difference engines that identify the list of changed files and directories between two snapshot copies of the same volume. When VCT is enabled for a D-NAS policy, NetBackup does not perform any file system tracking for backup or index of NAS volumes. Instead, NetBackup relies solely on the change-list from the difference engine of the storage array to perform backup of files and directories. This process optimizes the backup process.