Dell DR4300e NetVault Backup - Best Practices for Setting up VTL Containers an - Page 19

Using and managing a NetVault Backup nVTL on a DR Series appliance General guidelines and best practices for using a NetVault Backup VTL on a DR Series appliance: • Only create enough media to cope with one full cycle of backups and the relevant retention policies. • Set the Automatically label BLANK media parameter to off (clear the check box) to prevent erroneous use of blank media and to ensure efficient use of available media within a tape pool. A tightly managed tape pool will ease the space-reclamation process. • To simplify the management of tape pools, pre-label media and assign a NetVault Backup media group label. Tapes will be reused properly within a tape pool and space reclamation can be performed in an orderly fashion. In our sample NetVault Backup VTL, we can now look at grouping the data that is to be backed up to work with media groups as target sets. For example, if we have 2TB of data to back up, the backup is processed on a weekly Full Backup basis, and the retention is 4 weeks, we need 8TB of media. With media at 100GB each, 80 pieces of media can be added to the target media group. The main reason for using media groups is so we can force the DR Series appliance to reuse media before using blank media. NetVault Backup's media selection algorithm is: • Target media in a drive • Target media in a slot • Target blank media • Target media marked for re-use As you can see, blank media would be used before media marked for reuse. If we do not reuse media, the DR Series appliance will never be able to recover the space. By reusing media, NetVault Backup overwrites the previous contents after the header has been updated and reuses available space that otherwise would not be reclaimable by the clean cycle of the DR Series appliance. Keeping spare media that is not grouped blank will keep the usage of the DR Series appliance unit as low as possible. Because the Automatically label BLANK media option is disabled, the backup may run out of media before it completes, especially if the data set is growing. This is the trade off when using a DR Series appliance; media management becomes necessary to ensure best use of the unit. 19 Best practices for setting up Dell VTL Container or NetVault Backup native virtual tape library (nVTL)