Database Reference
In-Depth Information
When no shared spfile is used, the following procedure needs to run across all instances and must contain the
same values. If a shared spfile is configured, you need only to run the commands from one instance:
•
Set a user upper-limit size to the recovery destination:
SQL> alter system set db_recovery_file_dest_size=10G scope=both;
•
Specify the recovery path destination:
SQL> alter system set db_recovery_file_dest='+DG_RONDB_ARCH' scope=both;
Figure
8-3
illustrates the concept of a centralized recovery area in a RAC database.
RONDB_1
RONDB_2
LGWR
ARCn
DBWn
DBWn
ARCn
LGWR
Fast Recovery Area (FRA) :
ASM,CFS,NFS
2
2
1
2
1
2
1
1
2
Online
Redo
logs
1
2
Archive
logs
Figure 8-3.
FRA settings
Following are a few useful database dynamic views that render a better understanding of FRA usage and other
specific details:
SQL> SELECT * FROM V$RECOVER_AREA_USAGE;
SQL> SELECT * FROM V$FLASH_RECOVERY_AREA_USAGE;
SQL> SELECT * FROM V$RECOVERY_FILE_DEST
Snapshot Control File Configuration
Beginning with 11.2.0.2, for any form of database control file backup operations, Oracle no longer acquires the
controlfile enqueue lock. This change requires snapshot control file accessibility to all instances in a RAC database,
in contrast to a single-instance database, to successfully complete a manual or auto control file backup operation.
When the snapshot control file is not accessible or doesn't exist across instances, the backup of control file operations,
including RMAN backups, will fail with an '
ORA-00245: control file backup operation failed
' error.
