Oracle® Real Application Clusters Installation Guide 11g Release 2 (11.2) for Linux and UNIX Part Number E24660-02 |
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This chapter describes server parameter file (SPFILE) placement and configuration in Oracle Real Application Clusters (Oracle RAC) environments. This chapter contains the following topics:
Server Parameter File Errors in Oracle RAC
See Also:
The Oracle Real Application Clusters Administration and Deployment Guide for more information about parameters, and for a discussion of parallel execution-related parameters in Oracle RAC data warehouse environmentsOracle Database uses parameter settings in parameter files to determine how to control various database resources. You can use two types of files for parameter administration: the server parameter file (SPFILE
) or one or more traditional client-side parameter files.
Oracle recommends that you manage parameters using an SPFILE
. If you use client-side parameter files, then Oracle does not preserve parameter changes made for self-tuning after shutdown.
By default, Oracle Database creates the init
parameter file (PFILE
) for each node based on one SPFILE
. You can change parameter settings in the SPFILE
file by using only Oracle Enterprise Manager or ALTER SYSTEM SET
SQL statements, because the server parameter file is a binary file. Do not try to edit this file manually.
Note:
Oracle recommends that you avoid modifying the values for self-tuning parameters; overriding these settings can adversely affect performance.If you are upgrading from a previous Oracle Database release, then review the following section about the server parameter file for Oracle RAC.
With Oracle Database 11g release 2 and later databases, Database Agent automatically maintains the SPFILE based on the value you specify in the srvctl command srvctl add/modify -p
spfile
, where spfile
is the name of the SPFILE. You do not need to create or maintain init
ORACLE_SID
.ora
files.
The default location of the server parameter file (SPFILE)
is in the following path:
$ORACLE_HOME/dbs/spfile$ORACLE_SID.ora
The default location of the server parameter file is inappropriate for Oracle RAC databases and Oracle ASM instances if you use storage on a node, because all instances must use the same server parameter file.
Instead, Oracle recommends that you use a PFILE
in this directory:
$ORACLE_HOME/dbs/init$ORACLE_SID.ora
This path is valid for each instance and it refers to a single, shared initialization parameter file. For example, if you use NFS storage, then on a Linux or UNIX system, the file should contain an entry similar to the following:
SPFILE='/nfs/db/oracle_dg/dbspfile'
However, if you use a cluster file system, then use the following file location:
On Linux and UNIX-based systems:
SPFILE='/shared_mount/dbname/spfiledbname.ora'
In this syntax example, the variable shared_mount
is the shared mount point, and the variable dbname
is the database name.
To use DBCA to create your database, and to use the server parameter file, start DBCA. When the Initialization Parameters page appears, select Create server parameter file (SPFILE) under the File Locations tab. When you have made this selection, then enter either a shared file system filename, or enter the storage path in the Server Parameters Filename field.
Note:
When you use DBCA to create the server parameter file, the defaultSPFILE
file name is $ORACLE_HOME/dbs/init$ORACLE_
SID
.ora
Oracle Database searches for your parameter file in the following order:
$ORACLE_HOME/dbs/spfile
sid
.ora
$ORACLE_HOME/dbs/spfile.ora
$ORACLE_HOME/dbs/init
sid
.ora
Migrate to the SPFile
by creating and editing the server parameter file using the procedures described in this section. This section contains the following topics:
For single-node cluster-enabled configurations, or if you are using Oracle ASM disk groups or a cluster file system, place the server parameter file in an Oracle ASM disk group or on a file system. Otherwise, place the server parameter file on a shared raw device that is at least 5 MB in size.
Migrate to the SPFILE
file by completing the following procedures:
Combine the initialization parameter files for all instances into one init
dbname
.ora
file, where dbname
is the name of the database, by copying all shared IFILE
contents as is. All parameters defined in your IFILE
parameter files are global. Therefore, create them in the format parameter=value, without SID
prefixes.
Copy all instance-specific parameter definitions from init
sid
.ora
files using the following syntax, where the variable sid
is the SID
of the instance:
sid.parameter=value
If you are using a cluster file system, then Oracle recommends that you use the following command to define the location of the new SPFILE, where spfile
is the name of the SPFILE:
srvctl modify database -p spfile
You can also create the server parameter file using the CREATE SPFILE
statement as in the following example:
CREATE SPFILE='?/dbs/spfile_dbname.ora' FROM PFILE='?/dbs/initdbname.ora'
If you use Oracle ASM, then you can use the following syntax to create the server parameter file, where disk_group_name
is the disk group name, db_uniquename
is the database name, dbname
is the database name, and Oracle_home
is the Oracle home path:
CREATE SPFILE='+disk_group_name/db_uniquename/spfiledbname.ora' FROM PFILE='Oracle_home/dbs/initdbname.ora'
These statements read your combined init
dbname
.ora
file that you created by merging your IFILEs, and then transfer the settings for the parameters from the merged file into your server parameter file.
Oracle recommends that you use the SPFILE
by using the PFILE
as a pointer to the SPFILE
. Do this by running the STARTUP
command as in the following example, where the SID variable sid
in the file init
sid
.ora
is the SID that you use in the SPFILE
entry from Step 3. For example:
STARTUP PFILE=$ORACLE_HOME/dbs/initsid.ora
If you use this STARTUP
command syntax, then Oracle Database uses the server parameter file entry specified in the file init
sid
.ora
.
Note:
With Oracle ASM 11g release 2 and later releases, theSPFILE
for the Oracle ASM instance can be stored in Oracle ASM. You can also place an Oracle ASM instance SPFILE
on a file system, or you can use a traditional client-side parameter file for each Oracle ASM instance.See Also:
The Oracle Automatic Storage Management Administrator's Guide for more information about administering an Oracle ASM instanceOracle Database reports errors that occur during server parameter file creation, or while reading the file during startup. If an error occurs during a parameter update, then Oracle records the error in your ALERT.LOG
file, and ignores subsequent parameter updates to the file. If this happens, then do either of the following:
Shut down the instance, recover the server parameter file, and restart the instance.
Enable the instance to continue running without regard for subsequent parameter updates.
Oracle Database displays errors for parameter changes that you attempt when you incorrectly use the ALTER SYSTEM SET
statement. Oracle Database does this when an error occurs while reading from or writing to the server parameter file.
See Also:
The Oracle Real Application Clusters Administration and Deployment Guide for more information about backing up theSPFILE