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AdministeringIn addition to administering the database server, you can tune performance, replicate data, and archive data.
Backup and Restore GuideThe HCL OneDB™ Backup and Restore Guide describes how to use the HCL® OneDB® ON-Bar utility to back up and restore database server data. This will enable you to recover your databases after data is lost or becomes corrupted due to hardware or software failure or accident.
Overview of backup and restoreThese topics provide an overview of backup and restore concepts. They also provide information about planning for backup and restore operations.
Backup and restore conceptsHCL OneDB™ provides two utilities for backing up and restoring database server data. Both utilities back up and restore storage spaces and logical logs. However, they support different features and it is important to know the differences. These topics explain basic backup and restore concepts for HCL® OneDB® database servers and compares the ON-Bar and ontape utilities.
Recovery systemA recovery system, which includes backup and restore systems, enables you to back up your database server data and later restore it if your current data becomes corrupted or inaccessible.
Logical-log backupA logical-log backup is a copy to disk or tape of all full logical-log files. The logical-log files store a record of database server activity that occurs between backups.
Manual and continuous logical-log backupsYou can manually back up logical logs or you can enable continuous logical-log backup.

Manual and continuous logical-log backups

You can manually back up logical logs or you can enable continuous logical-log backup.

A manual logical-log backup backs up all the full logical-log files and stops at the current logical-log file. You must monitor your logical logs carefully and start logical-log backups as needed.

To find out if a logical-log file is ready to be backed up, check the flags field of onstat -l. After the logical-log file is marked as backed up, it can be reused. When the flags field displays any of the following values, the logical-log file is ready to be backed up:

U------
U-----L

The value U means that the logical-log file is used. The value L means that the last checkpoint occurred when the indicated logical-log file was current. The value C indicates the current log. If B appears in the third column, the logical-log file is already backed up and can be reused.

U-B---L

The flag values U---C-L or U---C-- represent the current logical log. While you are allowed to back up the current logical log, doing so forces a log switch that wastes logical-log space. Wait until a logical-log file fills before you back it up.

If you turn on continuous logical-log backup, the database server backs up each logical log automatically when it becomes full. If you turn off continuous logical-log backup, the logical-log files continue to fill. If all logical logs are filled, the database server hangs until the logs are backed up. You can start continuous logical log backups by setting the ALARMPROGRAM configuration parameter in the onconfig file or by running an ON-Bar or ontape command.

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