About selecting media in robots
When NetBackup receives a request for a volume, it searches the NetBackup 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
| Order | Description |
|---|---|
|
1. |
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. |
|
2. |
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.
|
|
3. |
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:
|
|
4. |
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. |
|
5. |
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. |