Veritas NetBackup™ Administrator's Guide, Volume II
- NetBackup licensing models and the nbdeployutil utility
- About NetBackup licensing models
- About the capacity licensing model
- nbdeployutil utility options
- Creating and viewing the licensing report
- After creating a traditional licensing report
- After creating a capacity licensing report
- Reconciling the capacity licensing report results
- Additional configuration
- About dynamic host name and IP addressing
- About busy file processing on UNIX clients
- About the Shared Storage Option
- About configuring the Shared Storage Option in NetBackup
- Viewing SSO summary reports
- About the vm.conf configuration file
- Holds Management
- Menu user interfaces on UNIX
- About the tpconfig device configuration utility
- About the NetBackup Disk Configuration Utility
- Reference topics
- Host name rules
- About reading backup images with nbtar or tar32.exe
- Factors that affect backup time
- NetBackup notify scripts
- Media and device management best practices
- About TapeAlert
- About tape drive cleaning
- How NetBackup reserves drives
- About SCSI persistent reserve
- About the SPC-2 SCSI reserve process
- About checking for data loss
- About checking for tape and driver configuration errors
- How NetBackup selects media
- About selecting media in robots
- About selecting media in standalone drives
- About Tape I/O commands on UNIX
About selecting media in robots
When NetBackup receives a request for a volume, it searches the EMM database for the media ID. The external media ID should correspond to the NetBackup media ID.
A request for a volume includes the following attributes:
The media ID
The device density
The file name that is used to link to the device that is assigned.
Table: How NetBackup selects a volume in a robot describes the order in which NetBackup selects a volume in a robot.
Table: How NetBackup selects a volume in a robot
NetBackup searches the media catalog for a volume that is already mounted in a drive and meets the following criteria:
If a suitable volume is found, NetBackup uses it.
If NetBackup cannot find a mounted volume that satisfies all of the previous conditions, it checks the media catalog for any volume that is suitable.
If a suitable volume does not exist or if a suitable volume is at end of media (EOM), NetBackup assigns a new volume. NetBackup may assign a new volume even if a volume is not full (because NetBackup received an EOM message from the drive).
The new volume must meet all of the following criteria:
If more than one volume qualifies, NetBackup chooses the volume that was least recently used.
NetBackup then adds it to the media catalog and assigns it the specified retention level.
If there are no unassigned volumes of the requested type, the backup terminates with an error message that no media were available.
NetBackuptakes no action.