NetVault Plug-in for VMware 10.0.5

Full Backup: A Full Backup provides a backup of all allocated sectors on a virtual disk. Full Backups take longer to complete and consume more backup media. These backups serve as the base backup for future Incremental and Differential image-level backups.

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Differential Backup: A Differential Backup provides a backup of disk sectors that have changed since the last Full Backup. Differential Backups speed up recovery since the plug-in is only required to restore two savesets.

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Incremental Backup: An Incremental Backup provides a backup of disk sectors that have changed since the last Full, Differential, or Incremental Backup. Incremental Backups consume minimum storage space and are quicker to perform. However, data recovery can take more time depending on the number of savesets that the plug-in is required to restore.

Data backed up and restored for different disk types

The Plug‑in for VMware includes the following data in CBT-enabled backups and restores.

Table 1. Data backed up and restored for different disk types
Disk Type	CBT-enabled Full Image Backups	Incremental/ Differential Image Backups	Restore of CBT-enabled Full Image Backups	Restore of Incremental/ Differential Image Backups
Thin (Required space supplied and zeroed out on demand.)	Only used disk sectors are backed up.	Only changed disk sectors are backed up.	Only used sectors are restored.	Only used disk sectors are restored. Each sector is restored only once.
Zeroed Thick (All space allocated at creation time, unused part zeroed out on first write.)	Only used disk sectors are backed up.	Only changed disk sectors are backed up.	Only used sectors are restored.	Only used disk sectors are restored. Each sector is restored only once.
Eager Zeroed Thick (All space allocated and zeroed out at creation time.)	All disk sectors are backed up.	Only changed disk sectors are backed up.	The entire disk is restored.	The entire disk is restored. Each sector is restored only once.
Virtual Compatibility RDM	All disk sectors are backed up.	Only changed disk sectors are backed up.	The entire disk is restored.	The entire disk is restored. Each sector is restored only once.
Network File System (NFS)	All disk sectors are backed up.	Only changed disk sectors are backed up.	The entire disk is restored.	The entire disk is restored. Each sector is restored only once.

Image-level backups without CBT

The Plug‑in for VMware only supports Full image-level backups of virtual machines that do not use CBT.


	NOTE: Regardless of the disk provisioning type, image-level backups without CBT always back up the full disk size. Thus, backup of a 20GB thin-provisioned disk that only uses 2GB results in a 20GB backup. When you restore a non-CBT backup, all blocks are restored and allocated. After a disk is restored from a non‑CBT backup, subsequent CBT-enabled Full Backups back up the entire disk.

Important notes

The following table describes how the plug-in handles backups and restores of RDM disks.

Table 2. Considerations for RDM disks

RDM compatibility mode

VADP-based backups and restores

Physical compatibility mode

The disk is not backed up. Warning messages are written to the NetVault Backup binary logs and job logs.

Virtual compatibility mode (Independent disks)

The disk is not backed up. Warning messages are written to the NetVault Backup binary logs and job logs.

Virtual compatibility mode

The disk is backed up, but the data can only be restored to a flat file. Warning messages about the change in type are written to the NetVault Backup binary logs and job logs.

Optionally, you can omit the RDM disks in virtual compatibility mode during a restore.

To omit the RDM disks in virtual compatibility mode

Open the vmware.cfg file in a text editor. You can find this file in <NetVault Backup home>\config on Windows and <NetVault Backup home>/config on Linux.

Edit the following entry and set the value to false.

[Custom:RestoreRDMDisks]

Value=False

Save the file.