Enabling Archive Logs in a RAC Environment

2. Enable archiving:
   

   SQL> alter database archivelog;

3. Re-enable support for clustering by modifying the instance parameter cluster_database to TRUE from the current instance:
   

   SQL> alter system set cluster_database=true scope=spfile sid='racdb1';

4. Shutdown the local instance:
   

   SQL> shutdown immediate

5. Bring all instance back up using srvctl:
   

   $ srvctl start database -d racdb

6. (Optional) Bring any services (i.e. TAF) back up using srvctl:
   

   $ srvctl start service -d racdb

7. Login to the local instance and verify Archive Log Mode is enabled:
   

   $ sqlplus "/ as sysdba" SQL> archive log list Database log mode Archive Mode Automatic archival Enabled Archive destination USE_DB_RECOVERY_FILE_DEST Oldest online log sequence 83 Next log sequence to archive 84 Current log sequence 84

After enabling Archive Log Mode, each instance in the RAC configuration can automatically archive redologs!