GFS Example 2Suppose, the backup plan has the following tape options: • the Use a separate tape set option is selected • the Always use a free tape: For each full backup option is selected • the Always use a free tape: For each incremental backup option is cleared • the Always use a free tape: For each differential backup option is cleared. The example has only one difference from the previous one. That is selection of the Always use a free tape: For each full backup option. Below, the figure shows the deleted backups as actual, but demonstrates tape usage during the whole year for the GFS backup scheme in combination with the specified tape options. A number in the green rectangle marks an incremental backup created on Monday of the corresponding week of the year. If all the backups have to be kept during the year, the archive will require 28 tapes.
As the GFS backup scheme forces automatic deletion of the outdated backups, on the first Friday of the second year the tapes keep only the backups displayed in the next figure.
This figure demonstrates that the GFS Example 2 tape rotation scheme is more suitable for the case than GFS Example 1. The advantages of the GFS Example 2 tape rotation scheme for the analyzed case are the following:
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