How to Synchronize the Standby When there is a Big gap, and all Required Archived Logs are Lost
By AVargas on Jan 17, 2009
This post describes a situation that should not happen, having a standby out of synch and not having the required logs to close the gap.
If it is nice to have a procedure to deal with the situation, it is better to assure that archived logs are backed up on a schedule, and that the backup and cleanup script is automatically run every time a threshold of 20% free space on the archive log destination is reached before the next scheduled cleanup run.
In any case this technique is quite nice as it permit to re-synch the standby without needing to copy over the whole database, but only the blocks that were changed since the last standby SCN.
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