Mixing Retention Levels on Backup Volumes

By default, NetBackup stores each backup on a volume that has existing backups at the same retention level (the period is not checked). For example, if a backup has a retention level of 2, NetBackup stores it on a volume with backups at retention level 2. When NetBackup encounters a backup with a different retention level than the previous backup, it switches to an appropriate volume. Because volumes remain assigned to NetBackup until all the backups on them have expired, this approach results in more efficient use of media. Otherwise, for example, one small backup with an infinite retention prevents a volume from being reused, even if all other backups on the volume have expired.

If you want to mix retention levels on volumes, Host Properties > Master Server. Double-click a server and select Media. Select Allow multiple retentions per media or add ALLOW_MULTIPLE_RETENTIONS_PER_MEDIA to the bp.conf file.

If you keep only one retention level on each volume, do not use any more retention levels than necessary. This consumes resources and also increases the number of volumes required.