Cascading standby destinations
A cascaded standby database is a standby database that receives primary database redo indirectly, from a cascading physical standby database, rather than directly from a primary database. Cascading can reduce network bandwidth consumption by eliminating duplicate redo transmission over network links that are shared by more than one standby database. I used this method after I successfully created a physical standby from a backup that was running against another physical standby; all RMAN backups are configured to run against the physical standby. I needed to get some archivelogs to synch up primary with new standby; the archivelogs were no longer present on primary but were still located at the physical standby location. Therefore, to configure it so that I could successfully synchronize the new standby with primary, I did the following: Physical standby Database: db_unique_name = prmy_stb alter system set log_archive_config='DG_CONFIG=(prmy,prmy_stb,cscd_stb)'