Syncing Standby Database Using SCN Based Backup

In Oracle dataguard environment sometime we face issues with slow network pushing us into situation where the changes are piled up and normal redo shipping speed is not sufficient to cover the gap within required business timelines or might be archives/redo never shipped to standby database because of unavailability of standby database and you don’t have enough space on primary site to hold all required archives for recovery. In those situations you might take a decision clear space on primary site after moving archives to tape. Later on when standby will be available FAL service would not able to fetch the gap. One option is to restore those archives to standby site and register those archives while another option, which is of intermediate complexity in case we don’t have identical physical structure in both sites.

Today we will demonstrate recovery of standby database with SCN based incremental backup in environment where we have shared filesystem on primary site while standby database is hosting files in ASM.

1. Check the minimum SCN on standby database from where the changes need to be applied.
   

   Standby Site
   

   SQL> select min (checkpoint_change#) from v$datafile_header order by 1;

   MIN(CHECKPOINT_CHANGE#)
   ———————–
   109182027