Backup-archive clients can choose to back up their files using full or partial incremental backup. A full incremental backup ensures that clients' backed-up files are always managed according to policies. Clients are urged to use full incremental backup whenever possible.
If the amount of time for backup is limited, clients may sometimes need to use partial incremental backup. A partial incremental backup should complete more quickly and require less memory. When a client uses partial incremental backup, only files that have changed since the last incremental backup are backed up. Attributes in the management class that would cause a file to be backed up when doing a full incremental backup are ignored. For example, unchanged files are not backed up even when they are assigned to a management class that specifies absolute mode and the minimum days between backups (frequency) has passed.
The server also does less processing for a partial incremental backup. For example, the server does not expire files or rebind management classes to files during a partial incremental backup.
If clients must use partial incremental backups, they should periodically perform full incremental backups to ensure that complete backups are done and backup files are stored according to policies. For example, clients can do partial incremental backups every night during the week, and a full incremental backup on the weekend.
Performing full incremental backups is important if clients want the ability to restore files to a specific time. Only a full incremental backup can detect whether files have been deleted since the last backup. If full incremental backup is not done often enough, clients who restore to a specific time may find that many files that had actually been deleted from the workstation get restored. As a result, a client's file system may run out of space during a restore process.