NetBackup™ NAS Administrator's Guide
- Section I. About NAS backups
- Section II. Using NAS-Data-Protection (D-NAS)
- D-NAS overview
- D-NAS Planning and Tuning
- Pre-requisites for D-NAS configuration
- Volume multi-host backup
- Configure D-NAS policy for NAS volumes
- Using accelerator
- Using Vendor Change Tracking
- Replication using D-NAS policy
- Restoring from D-NAS backups
- Troubleshooting
- Section III. Using NDMP
- 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
- About enabling or disabling DAR
- Configuring NDMP backup to NetBackup media servers (remote NDMP)
- Configuring NDMP DirectCopy
- Accelerator for NDMP
- Remote NDMP and disk devices
- Using the Shared Storage Option (SSO) with NetBackup for NDMP
- NAS appliance information for NDMP
- Vendor-specific information
- EMC Celerra
- NetApp
- Using NetBackup with NetApp's Data ONTAP 8.2 cluster mode
- Using NetBackup with NetApp's Data ONTAP 8.2 cluster mode
- Backup and restore procedures
- Troubleshooting
- Using NetBackup for NDMP scripts
- Introduction to NetBackup for NDMP
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 | Description |
---|---|
File 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. |
Directory 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. |
Note:
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.
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