Step:-1 Before Changing the archivelog mode and Flashback Database check the status.
SQL> select log_mode,flashback_on from gv$database;
LOG_MODE FLASHBACK_ON
------------ ------------------
NOARCHIVELOG NO
NOARCHIVELOG NO
Step:-2 Stop the rac database service.
[oracle@bamisdbrac02 ~]$ srvctl status database -d misdbrac
Instance misdbrac1 is running on node bamisdbrac01
Instance misdbrac2 is running on node bamisdbrac02
[oracle@bamisdbrac02 ~]$
[oracle@bamisdbrac02 ~]$ srvctl stop database -d misdbrac
[oracle@bamisdbrac02 ~]$
Step:-3 Start the rac database in mount state.
[oracle@bamisdbrac02 ~]$ sqlplus
SQL*Plus: Release 19.0.0.0.0 - Production on Sun Nov 14 19:02:36 2021
Version 19.12.0.0.0
Copyright (c) 1982, 2021, Oracle. All rights reserved.
Enter user-name: /as sysdba
Connected to an idle instance.
SQL> startup mount
ORACLE instance started.
Total System Global Area 6.4425E+10 bytes
Fixed Size 37476752 bytes
Variable Size 1.0872E+10 bytes
Database Buffers 5.3419E+10 bytes
Redo Buffers 96739328 bytes
Database mounted.
SQL>
[oracle@bamisdbrac01 ~]$ sqlplus
SQL*Plus: Release 19.0.0.0.0 - Production on Sun Nov 14 19:02:04 2021
Version 19.12.0.0.0
Copyright (c) 1982, 2021, Oracle. All rights reserved.
Enter user-name: /as sysdba
Connected to an idle instance.
SQL> startup mount
ORACLE instance started.
Total System Global Area 6.4425E+10 bytes
Fixed Size 37476752 bytes
Variable Size 1.0335E+10 bytes
Database Buffers 5.3956E+10 bytes
Redo Buffers 96739328 bytes
Database mounted.
SQL>
Step:-4 Enable archive log mode and Flashback database
[oracle@bamisdbrac02 ~]$ srvctl status database -d misdbrac
Instance misdbrac1 is running on node bamisdbrac01
Instance misdbrac2 is running on node bamisdbrac02
[oracle@bamisdbrac02 ~]$
SQL> select FLASHBACK_ON from v$database;
FLASHBACK_ON
------------------
NO
SQL> archive log list
Database log mode No Archive Mode
Automatic archival Disabled
Archive destination /u01/app/oracle/product/19.3/db_1/dbs/arch
Oldest online log sequence 1772
Current log sequence 1773
SQL> select log_mode,flashback_on from gv$database;
LOG_MODE FLASHBACK_ON
------------ ------------------
NOARCHIVELOG NO
NOARCHIVELOG NO
SQL>
alter system set log_archive_dest_1='LOCATION=+FRA/' scope=both sid='*';
alter database archivelog;
alter system set db_recovery_file_dest_size=500G scope=both sid='*';
alter system set db_recovery_file_dest='+FRA' scope=both sid='*';
alter database flashback on;
Step:-5 Stop the RAC database service
[oracle@bamisdbrac02 ~]$ srvctl stop database -d misdbrac
Step:-6 Restart the RAC database
[oracle@bamisdbrac02 ~]$ srvctl start database -d misdbrac
[oracle@bamisdbrac02 ~]$ srvctl status database -d misdbrac
Instance misdbrac1 is running on node bamisdbrac01
Instance misdbrac2 is running on node bamisdbrac02
[oracle@bamisdbrac02 ~]$
Step:-7 Check Archivelog and flashback Status
SQL> select log_mode,flashback_on from gv$database;
LOG_MODE FLASHBACK_ON
------------ ------------------
ARCHIVELOG YES
ARCHIVELOG YES
SQL>
[oracle@bamisdbrac02 ~]$ sqlplus
SQL*Plus: Release 19.0.0.0.0 - Production on Sun Nov 14 19:11:38 2021
Version 19.12.0.0.0
Copyright (c) 1982, 2021, Oracle. All rights reserved.
Enter user-name: /as sysdba
Connected to:
Oracle Database 19c Enterprise Edition Release 19.0.0.0.0 - Production
Version 19.12.0.0.0
SQL> select log_mode,flashback_on from gv$database;
LOG_MODE FLASHBACK_ON
ARCHIVELOG YES
ARCHIVELOG YES
SQL>
