Change Oracle Database to ArchiveLog Mode

Steps to change the database to Archivelog Mode:

1. Login to the database server. Connect to sqlplus as sysdba

$sqlplus / as sysdba

2. Shutdown the database

SQL> shutdown immediate

3. Take a full database Backup (Cold Backup in this case)

4. Startup the database in mount stage

SQL> startup mount

5. Enable Archivelog mode

SQL> alter database archivelog;

6. Open the Database.

SQL> Alter database open;

7. Verify the changes.

SQL> archive log list;

Enable ArchiveLog Mode on Oracle RAC database fails with ORA-00265

On a test RAC environment, while archiving is being enabled, "ALTER DATABASE ARCHIVELOG" command errored with ORA-00265: instance recovery required, cannot set ARCHIVELOG mode

Below are the steps performed to enable Archivelog mode on a 3-node RAC database environment.

test0115:TEST1011 $ srvctl status database -d TEST101
Instance TEST1011 is running on node test0115
Instance TEST1012 is running on node test0116
Instance TEST1013 is running on node test0117
test0115:TEST1011 $
test0115:TEST1011 $ srvctl stop database -d TEST101


test0115:TEST1011 $ srvctl status database -d TEST101
Instance TEST1011 is not running on node test0115
Instance TEST1012 is not running on node test0116
Instance TEST1013 is not running on node test0117
test0115:TEST1011 $


test0115:TEST1011 $ srvctl start database -d TEST101 -o mount
test0115:TEST1011 $  srvctl status database -d TEST101
Instance TEST1011 is running on node test0115
Instance TEST1012 is running on node test0116
Instance TEST1013 is running on node test0117
test0115:TEST1011 $


test0115:TEST1011 $ sqlplus / as sysdba

SQL*Plus: Release 11.2.0.4.0 Production on Sat May 9 14:13:54 2020

Copyright (c) 1982, 2013, Oracle.  All rights reserved.


Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, Real Application Clusters and Automatic Storage Management options

SQL> select name,open_mode from gv$database;

NAME      OPEN_MODE
--------- --------------------
TEST101   MOUNTED
TEST101   MOUNTED
TEST101   MOUNTED

SQL>SQL> alter database archivelog;
alter database archivelog
*
ERROR at line 1:
ORA-00265: instance recovery required, cannot set ARCHIVELOG mode

Solution:
=========

1. Shutdown the database cleanly

SQL> shutdown immediate (on 3 RAC nodes)

2. Startup the database in mount stage

SQL> startup mount

3. Enable Archivelog mode

SQL> Alter database archivelog;

Database altered.

4. Open the database

SQL> Alter database open.

5. Verify archielog mode is enabled.

SQL> ARCHIVE LOG LIST;