NetBackup for VMware terminology


NetBackup for VMware terminology

Table: NetBackup for VMware terms lists the terminology that is used in NetBackup for VMware.

For further explanations of VMware terminology, refer to your VMware documentation.

Table: NetBackup for VMware terms



backup host

The backup host is a NetBackup client that performs backups on behalf of the virtual machines. (This host was formerly known as the VMware backup proxy server.) The backup host is the only host on which NetBackup client software is installed.

As an option, the backup host can also be configured as a NetBackup master server or media server.

The backup host is referred to as the recovery host when it performs a restore.

See NetBackup for VMware components.

backup media server

A media server that operates as a backup host.


In NetBackup for VMware, the datastore is a disk that contains the virtual machines files.

datastore cluster

A collection of datastores that can be managed as a single unit. VMware Storage DRS manages the storage resources of the cluster.

discovery host

Discovers the virtual machines, filters them by the rules in the Query Builder, and returns a list of virtual machines to be selected for backup. The discovery host is used only for automatic selection of virtual machines.

Can be the same host as the VMware backup host.

See NetBackup for VMware components.

guest OS

An operating system that runs on a virtual machine.


A software virtualization layer that lets different operating systems run simultaneously on the same physical computer. The VMware hypervisor is vSphere, which runs on the ESX server host.

independent disk

A virtual disk that cannot be captured with a snapshot. An independent disk can be configured as either persistent or temporary.


NetBackup for VMware cannot back up the data on an independent disk. The backup succeeds but the backup image contains no data for the independent disk. If you restore the disk from the backup, the independent disk is restored to its original allocation size but contains no data. For example, the Windows swap file can reside on an independent disk, and is consequently not included in the virtual machine backup.

To back up the data on an independent disk, install a NetBackup client on the virtual machine.

See NetBackup for VMware: notes and restrictions.


The combination of rules in the policy's Query Builder, by which NetBackup selects virtual machines for backup. A query consists of one or more rules.

Query Builder

For creating filtering rules for automatic selection of virtual machines for backup. The Query Builder is on the Clients tab of the NetBackup policy.

query rule

A single statement in a query, by which NetBackup selects virtual machines for backup.

An example of a query rule is: Displayname Contains "finance"

Raw device mapping (RDM)

Allows a virtual machine to directly access physical disks (on Fibre Channel or iSCSI). RDM allows the OS and applications in the virtual machine to have pass-thru access to raw devices.

NetBackup for VMware cannot back up an RDM disk. NetBackup client software must be installed in the virtual machine.

See About VMware raw device mapping (RDM).

recovery host

See backup host.

virtual machine

An execution environment that the hypervisor creates for the computer hardware. The resulting virtualized environment allows different operating systems to run simultaneously on the same physical computer.

virtual network

A logical network that allows the exchange of data between virtual machines. A virtual network uses a virtual switch (VMware vSwitch). A virtual network can be connected to a physical network.

vmdk file

In a VMware ESX server, one or more vmdk files make up the disk image or virtual drive in a virtual machine. The .vmdk files contain the operating system, applications, and data in the virtual machine.

VMware Tools

Installed inside each VMware virtual machine. Enhances the virtual machine performance and adds backup-related functionality.

VMX datastore

Sometimes called the vmx directory or configuration datastore. Contains the configuration files that describe the virtual machine, such as .vmx files. During a backup of a virtual machine snapshot, vmdk writes are also cached on this datastore. Note that a separate vmx datastore is not a VMware requirement.


VMware vStorage APIs enable data protection features for more efficient use of storage capacity. NetBackup can use vStorage to back up the latest vSphere environments as well as to back up earlier VMware environments.

See About NetBackup for VMware

See Notes on troubleshooting NetBackup for VMware

Terms of use for this information are found in Legal Notices.



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