Dell DR4100 Symantec Backup Exec - Setting Up the DR Series System on Symantec - Page 99

In the previous example at the end of the 5-week cycle the 1st week retires and frees up media to be reused or recycled which once processed will allow the DR to reclaim the physical space associated with the virtual media. Since the smallest data set footprint resulting from the change rate is 2TB in each incremental iteration we create our media at 800GB increments and add as we grow. For this example the initial Virtual Tape Library would be created with 152 (121TB divided by 800GB) pieces of media at 800GB for each piece media. 20TB Total initial footprint with a 10% change rate Week Logical Size 1 24.2TB 2 24.2TB 3 24.2TB 4 24.2TB 5 24.2TB Total 121TB Pre-Deduplication 10% Change Rate Logical Logical Full Metrics Incremental Metrics 20TB 2TB 20TB 2TB 20TB 2TB 20TB 2TB 20TB 2TB C.2.4 Media retention and grouping Due to the nature of Virtual Tape Libraries media must be managed in order to insure that physical capacity is reclaimed in an orderly fashion to avoid running out of space and disrupting operations. Media must be grouped within the data management application, such as NetVault Backup, in a way that full data sets are targeted to separate media as incremental data and they in turn are grouped by data sets that expire within the same period or that share the same recovery point objective. This ensures that media can be reused effectively so that when full all incremental data expire the logical space can be reconciled thus enabling the physical space to be reclaimed. C.2.5 VTL media count guidelines Type Capacity Max number of Tapes supported LTO-4 800GiB 2000 LTO-3 400GiB 4000 99 Setting Up the Dell™ DR Series System on Symantec™ Backup Exec™ | April 2015