If the log volumes of the original instance are not damaged, and you can use operating system tools to copy their content to the log volumes of the standby instance, then you can start the standby instance without losing data and in a state from the past.
· You have set up a standby instance.
· The standby instance has not been in the operational state ONLINE since it was last initialized.
· The log volumes of the original instance are not damaged.
· The number of log volumes and their size are the same in both instances.
· The original instance is in the operational state OFFLINE.
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1. If the log backups are imported automatically from the original instance into the standby instance, then cancel the imports (recover_cancel).
2. Use operating system tools to copy the log volumes from the original instance to the standby instance.
3. Import any missing log backups from the original instance into the standby instance.
You can now start operating the standby instance as an active instance.
You can also start the standby instance in a state from a time chosen in the past.
To do this in the Database Manager GUI, choose Instance ® Restart Until.
To do this in the Database Manager CLI, use the command db_online –u.