When the NetBackup master server is configured to perform a differential-incremental backup, NetBackup backs up all files that have changed since the last successful backup.

Differential-incremental backups can be configured to use either the date and time stamp or the archive bit. If the date and time stamp is used, the differential-incremental backup includes all files with date and time stamps that are more recent than the last full or incremental backup. If the archive bit is used, the differential-incremental backup includes all files that have their archive bit set. Archive bits are cleared on differential-incrementals if all files are successfully backed up.

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