Incremental Backups

Overview

An incremental backup contains only data that is new or has changed since the last backup, regardless of the type. On average, incremental backups consume far less media and place less of a burden on resources than full backups.

The following illustration clarifies the nature of full and incremental backups. For simplicity, assume there is a file system that contains six files as represented in the figure.

Note that the File System above could also represent database tables, Active Directory objects and attributes, etc.

Backup #1 is a full backup and therefore writes all the data, changed and unchanged, to the backup media. Backups #2 through #n-1 are incrementals and only back up those files that have changed since the time of the last backup, regardless of the type. For example, files A, B, and E changed after the full backup and were therefore backed up in Backup #2. Backup #4 backed up files A and D because both files were modified sometime after Backup #3 occurred. File F did not change; hence, it was not backed up in any of the incremental backups, but it was included in both full backups, which, by definition, back up everything.

For the DB2, DB2 DPF, Informix, Oracle, Oracle RAC and SAP iDataAgents, Incremental backup works as described in differential backups. See Differential Backups for information on Incremental backups for these iDataAgents.

Start an Incremental Backup

  1. From the CommCell Browser, expand Client Computers by double-clicking Client Computers | iDA File System | defaultBackupSet. The default and other subclients (if available) are displayed on the right-hand windowpane.
  2. To back up the default subclient, right-click the subclient, and click Backup.
  3. From the Backup Options dialog box, select Run Immediately.
  4. Select Incremental backup.
  5. Click OK.

    You can track the progress of the job in the Job Controller.