DB version: 19c
OS : Oracle Linux 8.4
I am a bit of a newbie when it comes to Dataguard.
As I understand, in a dataguard configuration, the archived redo logs are 'shipped' from primary to the standby. All dataguard setups in my shop are of Active Data guard configuration.
In my shop, I have noticed that, for Dataguard setups, the archive logs are backed up to tape at both the primary and physical standby sides.
i.e, there are hourly archive log backups between 10 am till 6pm (so, 9 times a day) at both primary and standby sides.
And the archivelog backup command is like below
backup
filesperset 25
format 'xyz.dbf'
archivelog all
delete input;
If the archivelogs are backed up at the primary side, why should the archivelogs at standby side be backed up as well, given that those archived logs are same ?
Isn't that a waste of space in the backup media (Tapes in my shop's case) ?
At the primary side
SQL> select count(*) from v$archived_log where status = 'A';
COUNT(*)
----------
4940
SQL> select count(*) from v$archived_log where status = 'A' and name is not null;
COUNT(*)
----------
4940
At the standby side
SQL> select count(*) from v$archived_log where status = 'A';
COUNT(*)
----------
0
SQL> select count(*) from v$archived_log;
COUNT(*)
----------
4928