1. stop the database service.
srvctl stop database -d RAC
2. start the database in mount state.
srvctl start database -d RAC -o mount
3. enable archive log mode.
SQL> alter database archivelog; Database altered.
4. Restart the database service (using srvctl)
srvctl stop database -d RAC srvctl start database -d RAC
5. set the archive destination to a ASM DISK
SQL> alter system set log_archive_dest_1='LOCATION=+ARCH/' scope=both sid='*'; System altered. SQL> archive log list Database log mode Archive Mode Automatic archival Enabled Archive destination +ARCH Oldest online log sequence 724 Next log sequence to archive 726 Current log sequence 726 SQL> alter system switch logfile; System altered.
