RMAN,Data Guard and Archive log deletion

Question

Our DG environment is running Oracle 11g R2
we have a 3 node DG environment with
A being the Primary
B and C being Active Data Guard Standbys
Backups are taken off of B and go directly to tape.
Standby Redo Logs and Fast Recovery Area are being used
Taking recommendation from "Using Recovery Manager with Oracle Data Guard in Oracle Database 10g"
RMAN Setting on Primary ("A")
CONFIGURE ARCHIVELOG DELETION POLICY TO APPLIED ON STANDBY
RMAN Setting on Standby ("B") where Backup is done
CONFIGURE ARCHIVELOG DELETION POLICY TO NONE
RMAN Setting on other Standby ("C")
CONFIGURE ARCHIVELOG DELETION POLICY TO APPLIED ON STANDBY
How can we know what archive logs are eligible to be deleted from "A" and "C" ?
When does the delete take place?
How can we tell when the archive logs are being deleted from "A" and "C" ?

Answer 1

Dear user10260925,
The documentation that you have read is reliable but insufficient.
The Oracle can manage the archivelog directory and knows which one is eligible for the deletion. Those stuff you have posted in here has been taken from the online documentation and is supported and can be used when the Oracle knows and manages the archivelogs. That is simply called the flash recovery area. Please read about the FRA in this very moment.
Under normal circumstances people in the industry uses some scripts to achive the archivelog deletion on the standby system.
Here is a useful example to you;
# Remove old archivelogs
00,30 * * * * /home/oracle/scripts/delete_applied_redo_logs_OPTSTBY.sh
vals3:/home/oracle#cat /home/oracle/scripts/delete_applied_redo_logs_OPTSTBY.sh
export ORACLE_SID=optstby
export ORACLE_HOME=/oracle/product/10.2.0/db_1
cd /db/optima/archive/OPTPROD/archivelog
/oracle/product/10.2.0/db_1/bin/sqlplus "/ as sysdba" @delete_applied_redo_logs.sql
grep arc delete_applied_redo_logs.lst > delete_applied_redo_logs_1.sh
chmod 755 delete_applied_redo_logs_1.sh
sh delete_applied_redo_logs_1.sh
rm delete_applied_redo_logs_1.sh
rm delete_applied_redo_logs.lst
vals3:/home/oracle#cd /db/optima/archive/OPTPROD/archivelog
vals3:/db/optima/archive/OPTPROD/archivelog#cat delete_applied_redo_logs.sql
set echo off
set heading off
spool /db/optima/archive/OPTPROD/archivelog/delete_applied_redo_logs.lst
select 'rm -f ' || name from v$archived_log where applied = 'YES';
spool off
exit
vals3:/db/optima/archive/OPTPROD/archivelog#Hope That Helps.
Ogan