Enable/Disable Archive Log Mode in 11gR2 RAC database

Environment
2-node 11.2.0.2 Oracle RAC on OEL 5.5x64bit platform

Problem
The RAC database was created with archive log mode enabled, which generated a lot of archive log files during data import.

Cause
Archive log mode generated many archive log files.

Solution
Our business requirements allow us to disable archive log mode in this 2-nodes Oracle RAC database.  We could re-enable it later.
Related links:

• Enabling Archive Logs in a RAC Environment - (Oracle11g) by Jeff Hunter 
• Archivelog Mode On RAC
• Enable Archivelog and Flashback in RAC Database

[oracle@node2~]$ more typescript

Script started on Tue 28 Dec 2010 03:49:44 PM EST
[oracle@node2~]$ sqlplus / as sysdba


SQL*Plus: Release 11.2.0.1.0 Production on Tue Dec 28 15:49:49 2010


Copyright (c) 1982, 2009, Oracle.  All rights reserved.




Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
With the Partitioning, Real Application Clusters, OLAP, Data Mining
and Real Application Testing options


SQL> alter system set cluster_database=false scope=spfile sid='node2';


System altered.


SQL> exit
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
With the Partitioning, Real Application Clusters, OLAP, Data Mining
and Real Application Testing options
[oracle@node2~]$ ssh node1
srvctl stop database -d node -o immediate


[oracle@node2~]$ sqlplus / as sysdba


SQL*Plus: Release 11.2.0.1.0 Production on Tue Dec 28 15:51:14 2010


Copyright (c) 1982, 2009, Oracle.  All rights reserved.


Connected to an idle instance.


SQL> startup mount;
ORACLE instance started.


Total System Global Area 3.1467E+10 bytes
Fixed Size                  2241960 bytes
Variable Size            1.5234E+10 bytes
Database Buffers         1.6173E+10 bytes
Redo Buffers               57962496 bytes
Database mounted.
SQL> archive log list;
Database log mode              Archive Mode
Automatic archival             Enabled
Archive destination            /u12/ora_arc
Oldest online log sequence     1677
Next log sequence to archive   1678
Current log sequence           1678




SQL> alter database noarchivelog;


Database altered.


SQL> alter system set cluster_database=true scope=spfile sid='node2';


System altered.


SQL> shutdown immediate;
ORA-01109: database not open




Database dismounted.
ORACLE instance shut down.
SQL> exit
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
With the Partitioning, Real Application Clusters, OLAP, Data Mining
and Real Application Testing options
[oracle@node2~]$ srvctl start database -d node
[oracle@node2~]$ sqlplus / as sysdba


SQL*Plus: Release 11.2.0.1.0 Production on Tue Dec 28 15:58:31 2010


Copyright (c) 1982, 2009, Oracle.  All rights reserved.




Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
With the Partitioning, Real Application Clusters, OLAP, Data Mining
and Real Application Testing options


SQL> archive log list;
Database log mode              No Archive Mode
Automatic archival             Disabled
Archive destination            /u12/ora_arc
Oldest online log sequence     1679
Current log sequence           1680
SQL> exit
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
With the Partitioning, Real Application Clusters, OLAP, Data Mining
and Real Application Testing options


Script done on Tue 28 Dec 2010 03:58:46 PM EST