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Related Documents
Conventions
New Storage Features for Oracle Database 11g Release 2 (11.2)
For more information about using Oracle Enterprise Manager to manage Oracle ASM, see Chapter 9, "Managing Oracle ASM with Oracle Enterprise. For more information about using Oracle Enterprise Manager to manage Oracle ASM, see "Oracle ASM Support Workbench" on page 9-25.
New Storage Features for Oracle Database 11g Release 1 (11.1)
For more information about Oracle ASM Fast Mirror Resync, see "Oracle ASM Fast Mirror Resync" on page 4-27. For more information about Oracle ASM rolling upgrade, see "Using Oracle ASM Rolling Upgrade" on page 3-21.
Overview of Oracle Automatic Storage Management
This chapter describes Oracle Automatic Storage Management (Oracle ASM) concepts and provides an overview of Oracle ASM features. Oracle ASM also uses the Oracle Managed Files (OMF) feature to simplify database file management.
Understanding Oracle ASM Concepts
For information about using Oracle Enterprise Manager, see Chapter 9, "Managing Oracle ASM with Oracle Enterprise Manager." For information about the ASMCMD command-line interface, see Chapter 12, "Oracle ASM Command-Line Utility."
About Oracle ASM Instances
In response, the Oracle ASM instance provides the file extent map information to the database instance. Multiple nodes that are not part of an Oracle ASM cluster cannot share a disk group.
About Oracle ASM Disk Groups
About Mirroring and Failure Groups
Fault groups are used to place mirrored copies of data so that each copy on disk is in a different fault group. You define fault groups for a disk group when you create an Oracle ASM disk group.
About Oracle ASM Disks
If you omit the failure group specification, Oracle ASM automatically places each disk in its own failure group, except for disk groups that contain disks on Oracle Exadata cells. For more information about mirroring and fault groups, see "Oracle ASM Mirroring and Fault Groups" on page 4-23.
Allocation Units
The simultaneous failure of all disks in a failure group does not result in data loss. Once a disk group is created, you cannot change the redundancy level of the disk group.
About Oracle ASM Files
Oracle ASM automatically generates Oracle ASM filenames as part of file creation and tablespace creation. You can specify user-friendly aliases for Oracle ASM files and create a hierarchical directory structure for the aliases.
Extents
Oracle ASM Striping
File Templates
Understanding Oracle ASM Disk Group Administration
About Discovering Disks
About Mounting Disk Groups
About Adding and Dropping Disks
About Online Storage Reconfigurations and Dynamic Rebalancing
Oracle ASM rebalancing operations are controlled by the size of the disks in the disk group. When configuring your system's memory, you should consider your system's initial capacity and your plans for future growth.
Storage Resources for Disk Groups
Change the ownership of the device user and group such as grid:asmadmin For information about Oracle ASM privileges, see "About Oracle ASM Privileges" on page 3-23. The group must be owned by the OSDBA of the Oracle ASM instance defined at installation.
Oracle ASM and Multipathing
Recommendations for Storage Preparation
Oracle ASM is installed on Oracle's on-premises network infrastructure, separate from the on-premise Oracle database. When managing an Oracle ASM instance, administrative activity must be performed in the native Oracle network infrastructure.
Operating With Different Releases of Oracle ASM and Database Instances Simultaneously
You can use Oracle Enterprise Manager and SQL*Plus to perform Oracle ASM instance administration tasks. The SOFTWARE_VERSION column of V$ASM_CLIENT contains the software version number of the database or Oracle ASM instance for the selected disk group connection.
Configuring Initialization Parameters for an Oracle ASM Instance
When using different software versions, the database instance supports the Oracle ASM functionality from the earliest release in use. For more information about the V$ASM_CLIENT and V$ASM_* views, see “Views Containing Oracle ASM Disk Group Information” on page 6-1.
Initialization Parameter Files for an Oracle ASM Instance
Backing Up, Copying, and Moving an Oracle ASM Initialization Parameter File
For information about upgrading an Oracle ASM instance, see "Upgrading an Oracle ASM Instance Using Oracle Universal Installer" on page 3-17.
Setting Oracle ASM Initialization Parameters
Automatic Memory Management for Oracle ASM
10g Release 2 (10.2) functionality to manually manage Oracle ASM SGA storage, also run the ALTER SYSTEM SET SGA_TARGET=0 statement. You can then manually manage Oracle ASM storage using the information in "Oracle ASM Parameter Setting Recommendations" on page 3-6, which discusses Oracle ASM storage-based parameter settings.
Oracle ASM Parameter Setting Recommendations
If not specified, the behaviors of all automatic memory management parameters in Oracle ASM instances are the same as in Oracle Database instances.
ASM_DISKGROUPS
ASM_DISKSTRING
A NULL value causes Oracle ASM to look for a default path for all disks in the system to which the Oracle ASM instance has read and write access. Oracle ASM cannot use a disk unless all the Oracle ASM instances in the cluster can discover the disk through one of their own discovery strings.
ASM_POWER_LIMIT
Refer to your operating system specific installation guide for more information about the default search path. The names do not have to be the same on every node, but all disks must be discoverable by all the nodes in the cluster.
ASM_PREFERRED_READ_FAILURE_GROUPS
DB_CACHE_SIZE
DIAGNOSTIC_DEST
INSTANCE_TYPE
LARGE_POOL_SIZE
PROCESSES
REMOTE_LOGIN_PASSWORDFILE
SHARED_POOL_SIZE
Setting Database Initialization Parameters for Use with Oracle ASM
Managing Oracle ASM Instances
Administering Oracle ASM Instances with Server Control Utility
Using Oracle Restart
Starting Up an Oracle ASM Instance
By mounting the disk group in restricted mode, only one Oracle ASM instance can mount the disk group. For more information about user authentication, see "Authentication to Access Oracle ASM Instances" on page 3-22.
About Mounting Disk Groups at Startup
About Restricted Mode
Shutting Down an Oracle ASM Instance
If a database instance is connected to the Oracle ASM instance, the database instance will be aborted. For more information about user authentication on Oracle ASM instances, see "Authentication to Access Oracle ASM Instances."
Upgrading an Oracle ASM Instance With Oracle Universal Installer
Otherwise, applications will encounter I/O errors, and Oracle ACFS user data and metadata may not be flushed to storage until the Oracle ASM storage is fenced. Verify that the listener and Oracle ASM instance are running in the Oracle grid infrastructure home, and ensure that the Oracle Database instance and Oracle Enterprise Manager agent are running in the old database home.
Downgrading an Oracle ASM Instance
If the Oracle ASM 11g Release 1 (11.1) home page was not removed, the files should be available. If necessary, run the Network Configuration Assistant (NETCA) in Oracle ASM 11g Release 1 (11.1) Native from netca.
Active Session History Sampling for Oracle ASM
Update the Oracle ASM entry in /etc/oratab to point to the Oracle ASM 11g Release 1 (11.1) home. Oracle Enterprise Manager may need to be reconfigured after the Oracle ASM instance is downgraded.
Using Oracle ASM Rolling Upgrade
Connect to the Oracle ASM instance with SQL*Plus as a privileged user and issue the STARTUP command. Note that the rolling upgrade to 11g Release 2 (11.2) moves the Oracle ASM instance to 11g Release 2 (11.2) Oracle grid infrastructure home.
Patching Oracle ASM Instances
Authentication for Accessing Oracle ASM Instances
About Privileges for Oracle ASM
Using One Operating System Group for Oracle ASM Users
Using Separate Operating System Groups for Oracle ASM Users
The SYSASM Privilege for Administering Oracle ASM
The SYSDBA Privilege for Managing Oracle ASM Components
Creating Users with the SYSASM Privilege
Operating System Authentication for Oracle ASM
On Linux and UNIX systems, the default operating system group, labeled OSASM, OSOPER for Oracle ASM and OSDBA for Oracle ASM, is dba. On Windows systems, the default name specified by OSASM, OSOPER, and OSDBA is ora_dba.
Password File Authentication for Oracle ASM
Members of the OSASM group are authorized to connect using the SYSASM privilege and have full access to Oracle ASM, including administrative access to all disk groups managed by that Oracle ASM instance.
Migrating a Database to Use Oracle ASM
Oracle Database that stores database files on the operating system file system or on raw devices, then you can migrate some or all of your data files to Oracle ASM storage. You can use the following methods to migrate to Oracle ASM as described in this section:
Using Oracle Enterprise Manager to Migrate Databases to Oracle ASM
Using Oracle ASM allows you to realize the benefits of automation and simplicity in managing your database storage.
Using Oracle Recovery Manager to Migrate Databases to Oracle ASM
Best Practices White Papers on Migrating to Oracle ASM
This information includes how to create, modify, drop, mount, and unmount Oracle ASM disk groups. The database instances that use Oracle ASM can continue to function while you manage disk groups.
Disk Group Attributes
For information about the DISK_REPAIR_TIME attribute, see "Oracle ASM Fast Mirror Resync" on page 4-27. For information about the SECTOR_SIZE attribute, see "Specifying the Sector Size for Drives" on page 4-8.
Creating Disk Groups
In addition to the disk group attributes listed in this section, template attributes are also assigned to a disk group. You can display disk group attributes with the V$ASM_ATTRIBUTE view and the ASMCMD lsattr command.
Using the CREATE DISKGROUP SQL Statement
Specify the disks to be formatted as Oracle ASM disks that belong to the disk group. Additionally, the disk must be addressable and the original disk group must not be mounted.
Creating Disk Groups for a New Oracle Installation
After Oracle Restart is installed, use ASMCA to create the fra disk pool to store the quick recovery area files. You can also create the fra disk group using SQL*Plus or ASMCMD commands run from the Oracle Restart home page.
Specifying the Allocation Unit Size
Note that the data disk group is the disk group used to store the Oracle Cluster Registry (OCR) and voting disks in an Oracle Grid Infrastructure installation. To change the DB_FILE_MULTIBLOCK_READ_COUNT setting, use the ALTER SYSTEM SQL statement, as shown in Example 4–3.
Specifying the Sector Size for Drives
As shown in Example 4–4, you can use the SECTOR_SIZE attribute with the CREATE DISKGROUP SQL statement to specify the sector size of the disk on which the Oracle ASM disk group resides. Oracle Database SQL Language Reference for information about the disk group attributes and the CREATE DISKGROUP SQL.
Oracle Cluster Registry and Voting Files in Oracle ASM Disk Groups
The COMPATIBLE.ASM diskgroup compatibility attribute must be set to 11.2 or higher to store OCR or disk voting data in the diskgroup. Example 4–5 Using the QUORUM keyword CREATE DISKGROUP ocr_data NORMAL REDUNDANCY FAILGROUP fg1 DISK '/devices/diskg1' FAILGROUP fg2 DISK '/devices/diskg2' QUORUM FAILGROUP fg3 DISK '/devices/diskg3' ATTRIBUTE 'compatible.asm.
Altering Disk Groups
Adding Disks to a Disk Group
Because no FAILGROUP clauses are included in the ALTER DISKGROUP statement, each disk is assigned to its own failure group. ALTER DISK GROUP data1 ADD DISK '/devices/diska5' NAME diska5, '/devices/diska6' NAME diska6, '/devices/diska7' NAME diska7, '/devices/diska8' NAME diska8 ;.
Adding Volumes to Disk Groups
The ALTER DISKGROUP VOLUME SQL statements enable you to manage Oracle ADVM volumes, including the functionality to add, change, disable, enable, and drop volumes. If the volume hosts an Oracle ACFS file system, you cannot resize that volume with the SQL ALTER DISKGROUP statement.
Dropping Disks from Disk Groups
The statements in this example demonstrate how to drop disks from the diskgroup data1 described in “Example: Adding Disks to a Diskgroup” on page 4-12. The following example omits diska5 from diskgroupdata1, and also illustrates how multiple actions are possible with one ALTER DISKGROUP statement.
Intelligent Data Placement
Oracle ASM Configuration Assistant (ASMCA) supports Intelligent Data Placement by creating a template while changing a disk group. Oracle Enterprise Manager supports Intelligent Data Placement by Templates, which is launched by a disk group.
Resizing Disks in Disk Groups
To apply the new smart data placement policy to existing file contents, you can manually initiate a rebalance. For information about the details of Smart Data Placement in the View, see "Viewing Disk Region Information" on page 6-5.
Undropping Disks in Disk Groups
Manually Rebalancing Disk Groups
Therefore, if you have initiated multiple rebalances on different disk groups, then Oracle processes this operation serially. The REBALANCE clause (with the POWER and WAIT/NOWAIT keywords) can also be used in ALTER DISKGROUP commands that add, drop, or resize disks.
Tuning Rebalance Operations
Oracle ASM Disk Discovery
How A Disk is Discovered
CANDIDATE /devices/disk07 DISK06 LID /devices/disk06 DISK05 LID /devices/disk05 DISK04 LID /devices/disk04 DISK03 LID /devices/disk03 7 rye gekies.
Disk Discovery Rules
Improving Disk Discovery Time
Oracle may need to dynamically change the ASM_DISKSTRING before adding a disk so that the new disk is detected through this parameter. If your site uses a third-party ASMLIB vendor, the vendor may have discovery string conventions that you must use for ASM_DISKSTRING.
Managing Capacity in Disk Groups
The value is the total raw space for all disks in the largest failure group. The value is the total raw space for all disks in the two largest failure groups.
Negative Values of USABLE_FILE_MB
In the sample query output for the data disk group, the calculation is as follows:
Oracle ASM Mirroring and Disk Group Redundancy
Oracle ASM Mirroring and Failure Groups
If there are not enough online fault groups to satisfy the file mirroring (redundancy attribute value) specified in the disk group file type template, Oracle ASM allocates as many mirror copies as possible and then allocates the remaining mirrors when enough online fault groups are available. For information about specifying Oracle ASM disk group templates, see "Managing Disk Group Templates" on page 7-15.
Oracle ASM Failure Groups
A small number of failure groups, or failure groups of unequal capacity, can cause allocation problems preventing the full utilization of all available storage. For information about quorum error groups, see "Oracle Cluster Registry and Voting Files in Oracle ASM Disk Groups" on page 4-10.
How Oracle ASM Manages Disk Failures
Guidelines for Using Failure Groups
Failure Group Frequently Asked Questions
A simultaneous failure can occur if there is a failure of a piece of hardware used by multiple failure groups. This type of error usually forces a disk group disconnect if all disks are unavailable.
Oracle ASM Recovery from Read and Write I/O Errors
Oracle ASM consults the Partner Status Table (PST) to see if any of the disk's partners are offline. If too many partners are already offline, Oracle forces ASM to unmount the disk group.
Oracle ASM Fast Mirror Resync
In this example, the entire disk in failure group FG2 is taken offline and deleted after the time period specified by DISK_REPAIR_TIME has elapsed. OFFLINE without the DROPAFTER clause, the value specified for the DISK_REPAIR_TIME attribute on the disk group is used.
Preferred Read Failure Groups
Querying the V$ASM_OPERATION view while running any of these types of ALTERDISKGROUP. ONLINE Statements displays the name and status of the current operation you are performing.
Configuring and Administering Preferred Read Failure Groups
In this case, you can specify only one error group as a preferred read error group for each instance. Use the V$ASM_DISK_IOSTAT view to identify specific performance issues with read error groups preferred by Oracle ASM.
Performance and Scalability Considerations for Disk Groups
The ASM_PREFERRED_READ_FAILURE_GROUPS parameter must contain only disks that are local to the instance. ASM_PREFERRED_READ_FAILURE_GROUPS, then Oracle ASM first reads the copy located on the preferred read disk.
Determining the Number of Disk Groups
Performance Characteristics When Grouping Disks
Oracle ASM Storage Limits
Disk Group Compatibility
Overview of Disk Group Compatibility
Disk Group Compatibility Attributes
Setting Disk Group Compatibility Attributes
Valid Combinations of Compatibility Attribute Settings
The COMPATIBLE.ASM and COMPATIBLE.RDBMS disk group attributes are set to the default value of 10.1.
Using CREATE DISKGROUP with Compatibility Attributes
Using ALTER DISKGROUP with Compatibility Attributes
Viewing Compatibility Attribute Settings
Features Enabled By Disk Group Compatibility Attribute Settings
Reverting Disk Group Compatibility
Considerations When Setting Disk Group Compatibility in Replicated Environments
Managing Oracle ASM File Access Control for Disk Groups
For information on managing Oracle ASM File Access Control with ASMCMD commands, see "ASMCMD File Access Control Commands" on page 12-50. See "Viewing Access Control Information for Oracle ASM Files" on page 6-4 for information on views that provide details about Oracle ASM file access control.
About Oracle ASM File Access Control
See ALTER DISKGROUP SET PERMISSION and ALTER DISKGROUP SET OWNERSHIP in "Using SQL Statements to Set Disk Group Attributes for Oracle ASM File Access Control" on page 4-40. See ALTER DISKGROUP ADD USERGROUP in "Using SQL Statements to Set Disk Group Attributes for Oracle ASM File Access Control" on page 4-40.
Using SQL Statements to Set Disk Group Attributes for Oracle ASM File Access Control
For files that exist on a disk group before you set the Oracle ASM File Access Control disk group attributes, you must explicitly set the permissions and ownership of those existing files. Optionally, you can create user groups that are groups of database users that share the same access permissions to Oracle ASM files.
Using SQL Statements to Manage Oracle ASM File Access Control
If the user owns any files on the same Oracle ASM disk group, this command fails with an error unless the CASCADE keyword is specified. Only the file owner or the Oracle ASM administrator can change the permissions of a file.
Mounting and Dismounting Disk Groups
You can also use this statement to add a database user to an existing disk group immediately after setting the Oracle ASM file access control disk group attributes and before creating new files. In a clustered Oracle ASM environment in RESTRICTED mode, a disk group is mounted in single-instance exclusive mode.
Mounting Disk Groups Using the FORCE Option
A disk group number is not included in a permanent structure, but the current value can be viewed in the GROUP_NUMBER column of the V$ASM views. If you try to unmount a disk group that contains open files, the statement will fail unless you also specify the FORCE clause.
Checking the Internal Consistency of Disk Group Metadata
In clustered Oracle ASM environments, if the Oracle ASM instance is not the first instance to mount the disk group, using the MOUNT FORCE statement fails. If all disks are available, using the FORCE option causes the MOUNT command to fail.
Dropping Disk Groups
When you delete a disk group, Oracle ASM disassociates the disk group and removes the disk group name from the ASM_DISKGROUPS initialization parameter if a server parameters file is used. The disk group on which you perform this operation must not be mounted anywhere in the cluster.
Renaming Disks Groups
For the DROP DISKGROUP statement to succeed, the Oracle ASM instance must be started and the disk group mounted with none of the disk group files open. The statement does not specify INCLUDING CONTENTS, so the drop operation fails if the disk group contains files.
Overview of Oracle ACFS
Management with Oracle ACFS and Oracle ASM Dynamic Volume Manager (Oracle ADVM) provides support for all customer data and presents a common set of Oracle storage management tools and services across multiple vendor platforms and operating system environments as in Oracle Restart (single node) and cluster configurations. Oracle ACFS does not support any files that can be stored directly in Oracle ASM.
Understanding Oracle ACFS Concepts
Oracle ACFS can be accessed and managed using the native operating system's file system tools and standard application programming interfaces (APIs). For information about the mount registry, see "About the Oracle ACFS Mount Registry" on page 5-6.
About Oracle ACFS
About Oracle ACFS and Oracle Database Homes
Each Oracle database home must be created using a separate Oracle ACFS file system located under the acfsmounts mount point. Oracle ACFS file systems can also be configured for use as application homes and Oracle database homes.
About Oracle ASM Dynamic Volume Manager
One or more Oracle Database homes on Oracle ACFS can be created under the mount point. After installing the Grid Infrastructure Software and before installing the Oracle Database software with the Oracle Universal Installer (OUI), you can create an Oracle ACFS file system to be configured for use as an Oracle Database Home.
About the Oracle ACFS Driver Model
About the Oracle ACFS Mount Model and Namespace
About the Oracle ACFS Mount Registry
About Oracle ACFS Snapshots
As a result, an Oracle ACFS snapshot can support the online recovery of files that have been accidentally modified or deleted from a file system. Oracle ACFS file systems can be dynamically resized to accommodate additional file and snapshot storage requirements.
About Oracle ACFS and Backup and Restore
Oracle ACFS snapshot storage is maintained within the file system, eliminating the need to manage separate storage pools for file systems and snapshots. For information about using Oracle Enterprise Manager, see "Managing Oracle ACFS Snapshots with Oracle Enterprise Manager" on page 10-5.
About Oracle ACFS Integration with Oracle ASM
Before an Oracle ACFS file extent is modified or deleted, its current value is copied to the snapshot to preserve the point-in-time view of the file system. An Oracle ACFS snapshot can also be used as the source of a file system backup, as it can be created on demand to provide a current, consistent, online view of an active file system.
Understanding Oracle ACFS Administration
Oracle ACFS and File Access and Administration Security
Oracle ACFS and Grid Infrastructure Installation
Oracle ACFS and Grid Infrastructure Configuration
After creation, an Oracle ACFS file system can be mounted, after which it is accessible to authorized users and applications that perform file and file system operations. For information about managing Oracle ACFS file systems with Oracle Enterprise Manager, see "Creating Oracle ACFS Volumes and File Systems" on page 10-1.
Clusterware Resources and Oracle ACFS Administration
For an example of the specific actions required to create a new file system, see "Basic Steps for Administering Oracle ACFS" on page 13-1. For information about managing Oracle ACFS file systems with ASMCA, see "Managing Oracle ACFS File Systems with Oracle ASM Configuration Assistant" on page 11-11.
Oracle ACFS and Dismount or Shutdown Operations
Overview of Oracle ASM Dynamic Volume Manager
Oracle ADVM volumes can be created on demand from Oracle ASM disk group storage and dynamically resized as needed. Oracle ADVM supports all storage solutions supported by Oracle ASM, with the exception of NFS and Exadata storage.
Views Containing Oracle ASM Disk Group Information
Example 6-1 Viewing Disk Group Attributes Using V$ASM_ATTRIBUTE SQL> SELECT dg.name AS diskgroup, SUBSTR(a.name,1,18) AS name,. Example 6–2 Checking disk group compatibility with V$ASM_DISKGROUP SQL> SELECT name AS disk group, compatibility AS asm_compat, .
Viewing Oracle ASM File Access Control Information
For more information about Oracle ASM file access control, see "Managing Oracle ASM File Access Control for Disk Groups" on page 4-38.
Viewing Disk Region Information
DATA OCRFILE COARSE MIRROR COLD COLD DATA ONLINELOG COARSE MIRROR COLD COLD DATA PARAMETERFILE COARSE MIRROR COLD COLD DATA TEMPFILE COARSE MIRROR COLD COLD DATA XTRANSPORT COARSE MIRROR COLD COLD 15 izbranih vrstic.
Views Containing Oracle ACFS Information
Examples 6–14 show information displayed from the V$ASM_VOLUME view for volumes in the DATA disk group. Examples 6–14 show information displayed from the V$ASM_VOLUME_STAT view for volumes in the DATA disk group.
What Types of Files Does Oracle ASM Support?
About Oracle ASM Filenames
Oracle ASM file creation requests are either single file creation requests or multiple file creation requests.
Single File Creation Form
Multiple File Creation Form
Fully qualified File Name Form
Alias Oracle ASM Filename Forms
Oracle Database refers to database files by their alias filenames, but only if you create the database files with aliases. When a control file points to data files and online redo logs, it can use alias file names.
Creating a Tablespace in Oracle ASM: Using a Data File with an Alias Name
If you create database files without aliases and then add aliases later, the database refers to the files by their fully qualified file names. If you e.g. creates a tablespace and uses an alias file name for the data file, the V$DATAFILE view displays the alias file name.
Alias Oracle ASM Filename with Template Form
For more information about alias file names, see "Managing Alias Names for Oracle ASM File Names" on page 7-9. Creating and maintaining Oracle ASM templates is discussed in "Managing Disk Group Templates" on page 7-15.
Incomplete Oracle ASM Filename Form
Incomplete Oracle ASM Filename with Template Form
Creating and Referencing Oracle ASM Files in the Database
Creating Oracle ASM Files Using a Default File Location for Disk Group Specification
Using Oracle ASM Filenames in SQL Statements
Managing Alias Names for Oracle ASM Filenames
Adding an Alias Name for an Oracle ASM Filename
Renaming an Alias Name for an Oracle ASM Filename
Dropping an Alias Name for an Oracle ASM Filename
Dropping Files and Associated Aliases from a Disk Group
In Examples 7–7, the alias name for the file is used to remove both the file and the alias from a Disk Group. Example 7–7 Deleting Files and Associated Aliases from a Disk Group ALTER DISKGROUP data DROP FILE '+data/payroll/compensation.dbf';.
Managing Disk Group Directories
The restore does not delete the tablespace, but there is no reference to the tablespace or its data file in the restored database. In Example 7-8, the Oracle-managed (system-generated) file name is used to delete the file and all associated aliases.
Creating a New Directory
Assuming that no subdirectory exists under the +data/orcl directory, the SQL statement in Example 7–10 fails.
Renaming a Directory
Dropping a Directory
Accessing Oracle ASM Files with the XML DB Virtual Folder
Inside /sys/asm
You cannot create hard links to existing Oracle ASM files or directories with APIs such as DBMS_XDB.LINK. You cannot rename (move) an Oracle ASM file to another disk group or directory outside of Oracle ASM.
Using DBMS_FILE Transfer Utility for Oracle ASM
Within the disk group directories under /sys/asm, such as /sys/asm/DATA, you can store database files only in these subdirectories.
Managing Disk Group Templates
Template Attributes
The type of mirroring associated with the Mirroring column for normal, high, and external redundancy disk groups is listed in Table 7–5. MIRROR Two-way mirroring Three-way mirroring (Not allowed) HIGH Three-way mirroring Three-way mirroring (Not allowed) UNPROTECTED No mirroring (Not allowed) No mirroring.
Adding Templates to a Disk Group
Modifying a Disk Group Template
Dropping Templates from a Disk Group
Creating Tablespaces in Oracle ASM: Specifying Attributes with Templates
Overview of Oracle ASM Data Migration
Purpose of Oracle ASM Data Migration
This chapter describes how to migrate data into and out of Oracle Automatic Storage Management (Oracle ASM) storage with Recovery Manager (RMAN).
Basic Concepts of Oracle ASM Data Migration
Basics Steps of Data Migration to Oracle ASM Using RMAN
This step is described in "Preparing to Migrate the Database to Oracle ASM Using RMAN" on page 8-3. This step is described in "Migrating the Database to Oracle ASM Using RMAN" on page 8-5.
Preparing to Migrate the Database to Oracle ASM Using RMAN
The format clause specifies +DATA, which is the name of the Oracle ASM disk group to use for storing the database. If block change tracking is enabled for the database, optionally create a level 1 incremental backup that you can use later to restore the database copy.
Migrating the Database to Oracle ASM Using RMAN
If the database does not use a server parameter file, create one in Oracle ASM. If the database uses a recovery area, change the location of the recovery area to an Oracle ASM disk group.
Migrating a Database from Oracle ASM to Alternative Storage
Moving Data Files Between Oracle ASM Disk Groups Using RMAN
You can also specify the data file by the data file number and data file type. The TOCOPY option of SWITCH switches the data file to the most recent copy of the data file.
Oracle Automatic Storage Management Home Page
This chapter describes how to manage Oracle Automatic Storage Management (Oracle ASM) using Oracle Enterprise Manager to provision and manage data file storage.
Accessing the Oracle ASM Home Page in Single-Instance Oracle Databases
Accessing the Oracle ASM Home Page in Oracle RAC Databases
Configuring Oracle ASM Initialization Parameters with Oracle Enterprise Manager
Preferred read error groups (Oracle RAC environments only) (ASM_ . PREFERRED_READ_FAILURE_GROUPS initialization parameter).
Bringing Disks Online and Offline
You can also click Show SQL to view the SQL that Oracle Enterprise Manager uses for the online operation. You can also click Show SQL to see the SQL that Oracle Enterprise Manager uses for the offline operation.
Managing Oracle ASM Users with Oracle Enterprise Manager
Click OK to create the user, Cancel to cancel the process, or View SQL to view the SQL used by Oracle Enterprise Manager to create the user. Click OK to edit the user's properties, Rollback to cancel the process, or Show SQL to view the SQL used by Oracle Enterprise Manager to edit the user's properties.
Managing Disk Groups with Oracle Enterprise Manager
Click Create, and Oracle Enterprise Manager displays the Create Disk Group page similar to the page in Figure 9–6. Select the box to the left of each disk you want to include in the new disk group.
Adding Disks to Disk Groups
Click a link in the Name column to select the disk group to which you want to add disks. Operations are complete when the dropped disks no longer appear in the disk group. See.
Monitoring Disk Group Usage
Click the box in the Select column next to the drive you want to force mount and click Mount. In the Mount Force Confirmation dialog box, as shown in Figure 9-8, select the Force option and click Yes.
Administering Advanced Disk Group Properties
You can also click No to cancel the mount force operation and View SQL to review the SQL that Oracle Enterprise Manager uses to perform the mount force operation.
Configuring Disk Group Compatibility Attributes
Configuring Disk Repair Time
Configuring Smart Scan Compatibility
Configuring File Access Control
Managing Oracle ASM File Access Control with Oracle Enterprise Manager
Managing Directories, Files, and Aliases with Oracle Enterprise Manager
You can select a file with the Select field and then click Rename to rename the file, click Edit to change the properties of a file, or click Delete to remove a file. For more information about managing Oracle ASM files, folders, and aliases, see Chapter 7, "Managing Oracle ASM Files, Folders, and Templates".
Managing Disk Group Templates with Oracle Enterprise Manager
You can click Create to add a new template, click Edit to change a page, or click Delete to delete a template. Clicking Create displays the Create Template page and allows you to enter a name in the Template Name field.
Monitoring Oracle ASM Performance with Oracle Enterprise Manager
Monitoring General Oracle ASM Performance
Determine the display and refresh rate of the performance graphs with the Display and Refresh options.
Checking Disk Group Integrity
On the disk group management page, click Verify and Oracle ASM displays a confirmation dialog for the disk group verification operation. Select Check and Repair if you want Oracle ASM to attempt to repair errors that Oracle Enterprise Manager detects during the disk group consistency check.
Backing Up Oracle ASM Files with Oracle Enterprise Manager
Select Check Without Repair if you only want Oracle ASM to record disk group inconsistency information in the warning log. You can also select View SQL to review the SQL statements used by the disk group control operation.
Performing Bad Block Recovery with Oracle Enterprise Manager
If you are not logged in, the login page appears and you log in as the SYS user, connecting as SYSASM. Click the disk group name and Oracle Enterprise Manager displays the disk group home page for that disk group.
Migrating to Oracle ASM with Oracle Enterprise Manager
Oracle Enterprise Manager displays an Overview page where you can review all of your selections before starting the migration operation. After the migration job is complete, the Oracle ASM links may not appear immediately on the Oracle Enterprise Manager page.
Oracle ASM Support Workbench
When you continue, Oracle Enterprise Manager displays the Schedule page where you can specify a job name and a date and time when you want the migration job to start. You can wait for the links to appear after a subsequent refresh or restart the Oracle Enterprise Manager agent as follows:
