The working set backup method includes two options; Changed today and Last accessed in x days. The Changed today option was called Daily backup in previous versions of Backup Exec. You can perform backups using the Changed today method in addition to the media rotation scheme selected. The Changed today method backs up all files with today’s date (created or changed today). The Changed today method does not affect the files’ backup status because the archive bit is not reset.
If you select the Last accessed in x days method, you can then indicate in the Files accessed in x days field that you want to include data that has been accessed in a specific number of days.
This option is similar to a differential backup, in which files that have been created or changed since the last full backup are included; however, the difference lies in that you can also specify to include all files accessed within the last x number of days. This option can speed the recovery of a crashed server because you only need to restore the working set backup to get up and running again, and then restore the latest full backup at a later time (if necessary).
To effectively include the data needed to make your system operational after restoring a working set backup, specifying at least 30 days in the Files accessed in x days field is recommended. With a full/working set backup scheme, the non-full backups will require more media space than full/differential or full/incremental schemes. However, in environments where active data is migrated frequently between machines, or when restore times are especially critical, working set backups can make up the cost of extra media in time savings for restoring data.
See About backup methods.