Veritas NetBackup™ for NDMP Administrator's Guide
- Introduction to NetBackup for NDMP
- About NetBackup for NDMP
- Types of NDMP backup
- About assigning tape drives to different hosts
- Installation Notes for NetBackup for NDMP
- Configuring NDMP backup to NDMP-attached devices
- About Media and Device Management configuration
- About creating an NDMP policy
- Backup selection options for an NDMP policy
- About enabling or disabling DAR
- Configuring NDMP backup to NetBackup media servers (remote NDMP)
- Configuring NDMP DirectCopy
- About NDMP DirectCopy
- Using NDMP DirectCopy to duplicate a backup image
- Accelerator for NDMP
- Remote NDMP and disk devices
- Using the Shared Storage Option (SSO)
- Backup and restore procedures
- About NetBackup for NDMP logs
- NetBackup for NDMP troubleshooting suggestions
- About robot tests
- Using NetBackup for NDMP scripts
About enabling or disabling DAR
By default, NetBackup for NDMP is configured to use Direct Access Recovery (DAR) to restore files or directories. DAR is used somewhat differently for file restore than for directory restore.
The following table describes how DAR is used for file and directory restores.
Table: How DAR is used for file and directory restores
Type of restore
For each restore of files (not of directories), NetBackup automatically determines if the use of DAR speeds up the restore. NetBackup uses DAR only when it results in a faster restore.
For restore of directories, by default DAR is always used to restore a subdirectory but never used to restore the directory containing an entire image. For example, if /vol/vol0 contains the entire image, and /vol/vol0/dir1 is a subdirectory, DAR is used by default to restore /vol/vol0/dir1. But it is not used to restore /vol/vol0.
For restore of subdirectories, NetBackup does not attempt to gauge the effectiveness of using DAR. Unless DAR is manually disabled, NetBackup always uses DAR to restore subdirectories.
You may have to disable DAR if you have problems with DAR and your NDMP host is an older computer or is not running the latest NAS OS version.