Disk groups can be specified as archive log destinations in the LOG_ARCHIVE_DEST and LOG_ARCHIVE_DEST_n initialization parameters. When destinations are specified in this manner, the archive log file names are created in default subdirectories with unique names. However, all LOG_ARCHIVE_DEST_n parameters must have a unique string. To enter the same disk group more than once, subdirectories must be used. For example, you can set LOG_ARCHIVE_DEST_n as follows:
LOG_ARCHIVE_DEST_1 = 'LOCATION=+FRA/orcl/arc_1' LOG_ARCHIVE_DEST_2 = 'LOCATION=+FRA/orcl/arc_2' ...
If LOG_ARCHIVE_DEST is set to a disk group name, LOG_ARCHIVE_FORMAT is ignored. Unique filenames for archived logs are automatically created by Oracle Database under default subdirectories. If LOG_ARCHIVE_DEST is set to a directory in a disk group, LOG_ARCHIVE_FORMAT has its normal semantics for the file alias. The underlying file is still generated in the default directories for the disk group with a system generated name.
You can also set the DB_RECOVERY_FILE_DEST initialization parameter to a disk group destination. In Example 17-3, archive log files are generated with ARCHIVELOG mode enabled, DB_RECOVERY_FILE_DEST set to the +FRA disk group, and ORCL is the value of the DB_UNIQUE_NAME parameter.
Oracle Database Administrator's Guide for information about managing archived redo log files
Example 17-3 Archived log files in an Oracle ASM disk group
SQL> SHOW PARAMETER DB_RECOVERY_FILE_DEST NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ db_recovery_file_dest string +FRA SQL> SELECT SUBSTR(name,1,64) name FROM V$ARCHIVED_LOG; NAME ---------------------------------------------------------------- +FRA/ORCL/ARCHIVELOG/2013_06_24/thread_1_seq_112.260.818960623 +FRA/ORCL/ARCHIVELOG/2013_06_24/thread_1_seq_113.261.818978423 +FRA/ORCL/ARCHIVELOG/2013_06_25/thread_1_seq_114.262.818993031 +FRA/ORCL/ARCHIVELOG/2013_06_25/thread_1_seq_115.263.819032439 +FRA/ORCL/ARCHIVELOG/2013_06_25/thread_1_seq_116.264.819047121 +FRA/ORCL/ARCHIVELOG/2013_06_25/thread_1_seq_117.265.819064815 +FRA/ORCL/ARCHIVELOG/2013_06_26/thread_1_seq_118.266.819079417 ...