In the GFS media pool, a separate media set is created for each backup cycle: weekly, monthly, quarterly and yearly.
For each media set, you can set the data retention period. The retention period indicates for how long the data is protected from overwriting.
If you want to disable any media set(s), set their retention period to 0 (zero). No backups will be stored to the media set with zero retention period.
Click Advanced to configure the advanced media set options.