NetVault Plug-in for VMware 13.1 - User Guide

Full

To back up all allocated sectors on a virtual drive, select this option.

Incremental

To back up disk sectors that have changed since the last Full, Differential, or Incremental Backup, select this option.

Differential

To back up disk sectors that have changed since the last Full Backup, select this option.

Enable Change Block Tracking for virtual machine

By default, CBT is disabled for a virtual machine. If you want to perform Incremental or Differential Backups of virtual machines, you must enable CBT for the Full Backup that serves as the base backup for subsequent Incremental and Differential Backups.

To enable CBT on all virtual machines included in the backup job, select this check box. (You can also enable CBT on specific virtual machines by using the Enable Change Block Tracking method. For more information, see Enabling CBT on individual virtual machines.)

If you select this check box and the plug-in fails to change this setting on a virtual machine, a warning message is logged.

If you do not select this check box, the plug-in does not change the CBT setting on the virtual machines during backups. Depending on whether CBT is enabled or disabled, the plug-in uses the appropriate backup method (CBT-based Full, Incremental, or Differential or non-CBT Full Backup) to back up the virtual machines.

Note the following:

Perform File Level Indexing

To generate file-level indexes for all supported volumes that are included in the backup snapshot, select this option. File-level indexing lets you restore individual files and directories from Full, Incremental, and Differential image-level backups of virtual machines. For more information on how file-level indexing affects backups, see Configuring default settings.

File-level indexing is available to volumes that use the following file systems:

The plug-in also supports volumes managed by Logical Volume Manager (LVM) on Linux-based systems and Logical Disk Manager (LDM) on Windows-based systems as single or spanned disks.

File-level indexing does not affect the backup size. However, it increases the backup index size and the total backup time, which is why the option is cleared by default. The amount of time taken to perform file-level indexing depends on several factors, including the number of files, fragmentation of files on the volumes, network traffic, and load on the ESXi or vCenter Server.

If you selected an existing Backup Selection Set that was created using a version of the plug-in before 11.4.5, this option reflects the setting that you chose when you created the set. Before 11.4.5, this option was selected by default. If you want to use the new default setting, which clears this selection, you must browse the plug-in once on the NetVault Selections window.

To do so, complete the following steps:

2	Next to the Selections list, click .

Enable Active Block Mapping

ABM technology provides filters to remove unused blocks during backups. Removing the unused blocks reduces the backup size and the amount of data transferred over the network. You can use ABM with CBT to back up only active and changed blocks during Incremental and Differential Backups.

ABM is supported on the NTFS file system on basic disks and EXT file systems. ABM is not supported with XFS.

ABM is disabled by default. Selecting this check box enables ABM, which allows the plug-in to back up only those sections of the virtual drives that are active. ABM scans the disk and detects inactive blocks; these blocks are then omitted during backups.

If a backup job includes any unsupported disk types, this option is ignored for those disks.

Remove snapshots from previous backups

When you run a backup job, the plug-in creates a snapshot named “BKB_SNAP” on the virtual machine to back up the selected data. Regardless of whether the backup completes successfully or fails, the plug‑in removes the snapshot on job completion. The plug-in also removes the snapshot if the job is stopped or the parent or child processes are terminated for any reason. However, if a job exits abnormally, the cleanup process may fail to remove the snapshot. To address such cases, the plug‑in provides an option to delete the snapshot when you run the job next time.

You can select the Remove snapshots from previous backups check box to remove any existing snapshots when you run the current job. Only the snapshots named “BKB_SNAP” are removed from the virtual machines. This option does not remove any other snapshots that exist on the virtual machine.

Maximum Number of Parallel Streams

By default, the plug-in generates a single data stream for a backup job, and backs up the selected virtual machines in a sequential manner. To increase throughput and reduce overall backup time for image-level backups, you can configure the plug-in to perform parallel backups of multiple virtual machines.

This setting determines the maximum number of parallel data streams that can be generated for an image-level backup job. For example, if 10 virtual machines are included in a job, and you set this parameter to four, the plug-in tries to back up four virtual machines in parallel.

The actual number of parallel streams for a job depends on the following factors:

For parallel backups, the plug-in generates a parent process that coordinates the overall backup and individual child processes that perform the actual task of backing up the virtual machines. The maximum child processes that can be generated for a backup job is equal to the Maximum Number of Parallel Streams configured for the job. The parent and the child processes are all created on the NetVault Client on which the plug-in is running.

When a child process acquires a backup device and creates a backup stream, it is assigned a task to back up a virtual machine. After the task completes, the process is assigned the next task if there are any more virtual machines to be backed up. Each task is assigned a Task ID. A snapshot is generated only when a virtual machine is assigned to a child process.

When configuring Maximum Number of Parallel Streams, consider the following:

Automatic diagnose virtual machine on backup failure

To run predefined tests that can identify the cause of a virtual machine backup failure, select this check box.

For more information about the Diagnose method, see Diagnosing virtual machine issues.

You can access the Diagnostic Results dialog box from the View Logs page. The details are stored as log context objects.

Enable Restartable backups

This option allows you to restart a job that completes with some failed virtual machines. The restarted instance backs up only those virtual machines that failed previously; virtual machines that are backed up successfully are not included in the restarted instance.

When a restartable backup completes with some failed virtual machines, the plug-in generates a backup index for the completed virtual machines and sets the job status to Job Stopped. The log messages and log context show which virtual machines have failed for the job. When you restart the job later, the plug-in runs an Incremental Backup job to back up the failed virtual machines.

You can restart a job from the Job Status page. For more information about this method, see Restarting a backup job. A restarted instance does not back up virtual machines that are added to the host after the initial job is run.

Disable distribution of backup job to other VMware Backup Proxy

If you configured your environment to use the Distributed Jobs feature, select this check box to turn off the feature for a specific job. This option is disabled by default.

Enable Job Level Transport Mode

If you are using the Distributed Jobs feature and you want to set the transport mode manually at the job level, select this option, and then select the applicable Primary Transport Mode and Fallback Transport Mode.