Progress
Database Administration
Guide and Reference
Online Backups
An online backup lets you back up the database while it is in use. You must use PROBKUP to perform online backups. Perform an online backup if the database cannot be taken offline long enough to perform an offline backup. You can perform both full and incremental online backups.
When deciding whether to use online backups, consider the following:
- You can perform an online backup if after-imaging is enabled. See "After-Imaging," for more information about after-imaging.
- You cannot perform an online backup on a system running in single-user mode.
- When you perform an online backup of a database, the database engine automatically switches over to the next AI file. Before you start an online backup, you must make sure that the next AI file is empty. If the file is not empty, PROBKUP aborts and notifies you that it cannot switch to the new file. See "After-Imaging," for information about the AIMAGE EXTENT LIST qualifier with the RFUTIL utility.
- The PROQUIET utility allows you to put the database in a quiet state while users are connected. You can then use backup techniques without shutting down the database. However, no active use of the database is allowed while the database is quiet. This approach is useful when split-mirrors are used as a backup technique.
- When you begin an online backup, make sure that you properly mount the backup media. If the media is not properly mounted, the database engine cannot write header information to it. Until the database engine writes the header information, you cannot update the database. If you use more than one volume to back up the database, there is a similar delay each time you switch volumes.
- You cannot use the PROBKUP parameters Scan (-
scan
) or Estimate (-estimate
) for online backups.
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