Changes in This Release for Oracle Automatic Storage Management Administrator's Guide

Oracle ASM Filter Driver (Oracle ASMFD) is a kernel module that resides in the I/O path of the Oracle ASM disks. Oracle ASM uses the filter driver to validate write I/O requests to Oracle ASM disks.

The Oracle ASM Filter Driver rejects any I/O requests that are invalid. This action eliminates accidental overwrites of Oracle ASM disks that would cause corruption in the disks and files within the disk group. For example, the Oracle ASM Filter Driver filters out all non-Oracle I/Os which could cause accidental overwrites.

For more information about Oracle ASMFD, refer to "Oracle ASM Filter Driver".

This feature provides general enhancements to Oracle ASM, including:

• Revised version of the physical metadata replication point

  Oracle ASM now replicates physically addressed metadata, such as the disk header and allocation tables, within each disk. This enhancement ensures that Oracle ASM is more resilient to bad disk sectors and external corruptions. The disk group attribute PHYS_META_REPLICATED is provided to track the replication status of a disk group.

  For more information on the PHYS_META_REPLICATED attribute, refer to "PHYS_META_REPLICATED".

• Support for increased storage limits

  Oracle ASM now supports 511 disk groups. The maximum Oracle ASM disk size is now 32 petabytes (PB).

  For information about Oracle ASM size limits, refer to "Oracle ASM Storage Limits".

• The ALTER DISKGROUP statement has been updated with a REPLACE clause.

  For more information about replacing disks in a disk group, refer to "Replacing Disks in Disk Groups".

Oracle Flex ASM enables an Oracle ASM instance to run on a separate physical server from the database servers. Many Oracle ASM instances can be clustered to support a large number of database clients.

This feature enables you to consolidate all the storage requirements into a single set of disk groups. All these disk groups can be managed by a small set of Oracle ASM instances running in a single cluster.

Oracle Flex ASM supports only Oracle Database 12c Release 1 (12.1) and later releases.

For information, refer to "Managing Oracle Flex ASM".

Oracle ASM disk scrubbing checks logical data corruptions and repairs the corruptions automatically in normal and high redundancy disks groups. The feature is designed so that it does not have any impact to the regular input and output (I/O) operations in production systems. The scrubbing process repairs logical corruptions using the Oracle ASM mirror disks. Disk scrubbing uses Oracle ASM rebalancing to minimize I/O overhead.

The scrubbing process is visible in fields of the V$ASM_OPERATION view.

For more information, refer to "Scrubbing Disk Groups".

The disk resync enhancements enable fast recovery from instance failure and faster resync performance overall. Oracle ASM disk resync enables multiple disks to be brought online simultaneously or to control the speed of the resync operation. Oracle ASM disk resync has a resync power limit to control resync parallelism and improve performance. Disk resync checkpoint functionality provides faster recovery from instance failures by enabling the resync to resume from the point at which the process was interrupted or stopped, instead of starting from the beginning.

For more information about disk resync, refer to "Oracle ASM Fast Mirror Resync".

The even read feature distributes data reads evenly across all the disks in a disk group. For each I/O request presented to the system, there may be one or more disks that contain the data. With this feature, each request to read can be sent to the least loaded of the possible source disks.

Even read functionality is enabled by default on all Oracle Database and Oracle ASM instances of version 12.1 and higher in non-Exadata environments. The functionality is enabled in an Exadata environment when there is a failure. Even read functionality is applicable only to disk groups with normal or high redundancy.

For information about even read for disk groups, refer to "Even Read for Disk Groups".

Oracle ASM rebalance enhancements improve scalability, performance, and reliability of the rebalance operation. This feature extends the rebalance process to operate on multiple disk groups in a single instance. In addition, this feature improves support for thin provisioning, user-data validation, and improved error handling.

For more information about disk group rebalancing, refer to "Manually Rebalancing Disk Groups" and "Tuning Rebalance Operations".

This feature implements the infrastructure needed to address the bootstrapping issues of Oracle ASM shared password file in an Oracle ASM disk group. This feature solves the bootstrapping problem for storing shared Oracle ASM password files in a disk group.

For information about a shared password file in a disk group, refer to "Managing a Shared Password File in a Disk Group". For information about ASMCMD commands to manage an Oracle ASM or database instance password file in a disk group, refer to "ASMCMD Instance Management Commands".

This feature provides enhancements to Oracle ASM File Access Control on Windows platforms.

Oracle Database now supports the use of an Oracle home user, which can be specified at installation time. The Oracle home user is associated with an Oracle home and it cannot be changed after installation. Different Oracle homes on a system can share the same Oracle home user or use different Oracle home user names. For more information, refer to "About Oracle Home User on Windows".

You can now use access control to separate roles in Windows environments. With Oracle Database services running as users rather than Local System, the Oracle ASM access control feature is enabled to support role separation on Windows. In previous releases, this feature was disabled on Windows because all Oracle services run as Local System.

You can change the identity of an Oracle ASM user from one operating system (OS) user to another OS user without having to drop and re-create the user, which requires dropping all the files a user owns, which improves the manageability of Oracle ASM users and the files they own.

You can modify Windows file access controls while files are open using ASMCMD file access control commands, such as chgrp, chmod, and chown.

For more information about Oracle ASM File Access Control, refer to "Managing Oracle ASM File Access Control for Disk Groups". For information about Oracle ASM File Access Control ASMCMD commands, refer to "ASMCMD File Access Control Commands".

This feature enhances the rolling migration framework to apply oneoff patches released for Oracle ASM in a rolling manner.

You can use this feature in a clustered Oracle ASM 12c Release 1 (12.1) and higher environment to update one node at a time to the latest patch level without affecting the overall availability of the Oracle ASM cluster or the database clusters using Oracle ASM for storage. This feature improves database availability by migrating the database to another Oracle ASM instance before a shut down and upgrade operation.

For information, refer to "About Oracle ASM Rolling Patches".

This feature updates Oracle key management commands to unify the key management application programming interface (API) layer. The updated key management framework makes interacting with keys in the wallet easier and adds new key metadata that describes how the keys are being used.

This feature adds a new capability to store a credential file (wallet) in Oracle ASM disk groups. For information about file types supported by Oracle ASM, refer to "What Types of Files Does Oracle ASM Support?".

Oracle Enterprise Manager replaces Enterprise Manager Database Control for administering Oracle Automatic Storage Management. For more information, refer to Administering Oracle ASM with Oracle Enterprise Manager.

All SRVCTL commands have been enhanced to accept more meaningful and user-friendly keyword-style options instead of the single letter options. All new SRVCTL command line interface options added in this release support keyword-style options only and do not have single-letter equivalents. The previous style of using single-letter keyword options as existed in previous releases remain fully supported. In a future release, the singe-letter options may no longer be supported and customers may want to change their scripts to adapt the keyword-style command options.

Oracle Restart is a feature provided as part of Oracle Grid Infrastructure. Oracle Restart monitors and can restart Oracle Database instances, Oracle Net Listeners, and Oracle ASM instances. Oracle Restart is currently restricted to manage single instance Oracle Databases and Oracle ASM instances only, and is subject to desupport in future releases. Oracle continues to provide Oracle ASM as part of the Oracle Grid Infrastructure installation for Standalone and Cluster deployments.

For more information about the Oracle Restart deprecation announcement and its replacement, see My Oracle Support Note Doc ID 1584742.1 (https://support.oracle.com/epmos/faces/DocumentDisplay?id=1584742.1&displayIndex=1).

Oracle Database 12c and related technologies, such as Oracle Clusterware 12c, no longer support the use of raw (block) storage devices. This means that files must be moved to Oracle ASM before upgrading to Oracle Clusterware 12c.

Oracle ACFS in Oracle Grid 12c Release 1 (12.1.0.2) on Windows supports all database files, except for data files and redo logs in an Oracle Restart (standalone server) configuration. For support of database files on Windows, the COMPATIBLE.ADVM attribute must be set to 12.1.0.2.

For more information about database files on Oracle ACFS, refer to "About Oracle ACFS and Database Data Files".

Oracle Exadata on Linux supports Oracle ACFS in Oracle Grid 12c Release 1 (12.1.0.2). Oracle ACFS supports general purpose files as well as database files; however, Oracle ASM is the best practice for support of database files.

Oracle ACFS can be configured for use with the database, particularly to leverage Oracle ACFS snapshots for database testing and development. However, Oracle ACFS does not currently have the ability to push database operations directly into storage.

For more information about database files on Oracle ACFS, refer to "About Oracle ACFS and Database Data Files".

A total of 1023 read-only, read-write, or combination of read-only and read-write snapshot views are supported for each file system. For information about Oracle ACFS snapshots, refer to "About Oracle ACFS Snapshots".

Oracle ACFS supports Oracle Database file mapping views to the Oracle ASM device level. For information about file mapping views related to Oracle ACFS, refer to "Oracle ACFS Support for Oracle Database File Mapping Views".

Oracle ACFS encryption supports Oracle Key Vault as a key store. For information about using this feature with Oracle ACFS encryption, refer to "Oracle ACFS Encryption".

This feature introduces enhancements for Oracle ACFS, including:

• Oracle ACFS in Oracle Grid 12c Release 1 (12.1) supports all database files for Oracle Database 11g Release 2 (11.2.0.4) or later, except for data files and redo logs in an Oracle Restart (standalone server) configuration. For this feature, the COMPATIBLE.ADVM attribute must be set to 12.1 or later for the disk group that contains the Oracle ACFS file system.

  Using Oracle ACFS replication or encryption with database files on Oracle ACFS is not supported. For information about other replication options for database files on Oracle ACFS, refer to Oracle Data Guard Concepts and Administration and Oracle GoldenGate documentation. Oracle GoldenGate is an Oracle product sold independently of the Oracle Database. To encrypt database data files on Oracle ACFS, Oracle recommends Oracle Advanced Security. Oracle Advanced Security provides Transparent Data Encryption (TDE) to encrypt data files for entire tablespaces. For information about Transparent Data Encryption (TDE), refer to Oracle Database Advanced Security Guide.

• Oracle ACFS supports clusterwide, file granular fcntl advisory file locking while byte range locks continue to operate in node local mode.

• Oracle ACFS directory listing performance is improved for newly created directories.

• Oracle ACFS supports end-to-end storage visibility for files with the -d option of acfsutil info file. The -d option displays details about a file extent location, from the Oracle ACFS extent to the Oracle ASM devices in the disk group. For information, refer to "acfsutil info file".

• Oracle ACFS ASMCMD commands have enhanced syntax. For information about ASMCMD commands for Oracle ACFS, refer to "ASMCMD Volume Management Commands".

• Oracle ACFS supports unlimited expansions when resizing a file system in a disk group with ADVM compatibility set to 11.2.0.4 or higher.

• Oracle ACFS performance and scalability improvements for ls and find in a disk group with ADVM compatibility set to 11.2.0.4 or higher.

For more information about Oracle ACFS, refer to "Overview of Oracle ACFS"

High Availability NFS for Oracle Grid Infrastructure provides uninterrupted service of NFS V2/V3/V4 exported paths by exposing NFS exports on Highly Available Virtual IPs (HAVIP) and using Oracle Clusterware agents to ensure that the HAVIPs and NFS exports are always online. While base NFS supports file locking, HANFS does not support NFS file locking.

Oracle ACFS file system exports (using NFS) include Golden Images and patch updates applied to Oracle ACFS snapshots. Note that NFS is deployed with Oracle Grid Infrastructure servers in support of Oracle Grid Infrastructure client systems. Application VIP and NFS export resources are employed for Oracle ACFS and highly available NFS.

High Availability NFS can also be used as a general high availability solution for Oracle ACFS exported file systems.

For information about High Availability NFS for Oracle Grid Infrastructure homes, refer to "High Availability Network File Storage for Oracle Grid Infrastructure".

Oracle ACFS supports the creation of a snapshot from an existing snapshot in the same Oracle ACFS file system. In addition, snapshot conversions are enabled between read-only and read-write snapshots.

For information about Oracle ACFS snapshots, refer to "About Oracle ACFS Snapshots". For information about Oracle ACFS snapshot commands, refer to "Oracle ACFS Command-Line Utilities".

Tagging operations are available as C application programming interfaces (APIs), described in "Oracle ACFS Tagging Generic Application Programming Interface".

For information about Oracle ACFS tagging, refer to "Oracle ACFS Tagging". For information about Oracle ACFS tagging operations available through the acfsutil tag commands, refer to "Oracle ACFS Command-Line Tools for Tagging".

Oracle ACFS and Oracle ADVM resource support is enhanced for both performance and coverage. Oracle Clusterware (CRS) managed resource support is extended to include enhancements for Oracle ACFS Oracle homes, Oracle ACFS General Purpose file systems, and Oracle ADVM volumes in supporting Oracle Grid Infrastructure Server Oracle ACFS export (using NFS) configurations. SRVCTL has updates to commands for managing Oracle ACFS and Oracle ADVM resources.

For information about Oracle Clusterware resources and Oracle ACFS, refer to "Oracle Clusterware Resources and Oracle ACFS Administration".

The Oracle ACFS plugin functionality enables a user space application to collect just-in-time Oracle ACFS file and Oracle ADVM volume metrics from the operating system environment. Applications can use the Oracle ACFS plug-in infrastructure to create customized solutions that extend the general application file metric interfaces to include detailed Oracle ACFS file system and volume data.

For information about Oracle ACFS plugins, refer to "Oracle ACFS Plugins". For information about Oracle ACFS plugin commands, refer to "Oracle ACFS Command-Line Utilities". For information about the Oracle ACFS plug-in application programming interface, refer to "Oracle ACFS Plug-in Generic Application Programming Interface".

This feature enables the integration of Oracle Automatic Storage Management Cluster File System (Oracle ACFS) replication with Oracle ACFS auditing, encryption, and security.

For more information, refer to "Using Replication with Auditing_ Encryption_ and Security".

This feature provides auditing for Oracle ACFS security and encryption. In addition, this feature also generates an XML file containing Oracle ACFS audit trail data which can be imported by Audit Vault Server.

For more information, refer to "Oracle ACFS Auditing". For information about Oracle ACFS commands for auditing, refer to "Oracle ACFS Command-Line Tools for Auditing" and the acfsutil sec realm enable and acfsutil sec realm disable commands described in "Oracle ACFS Command-Line Tools for Security".

This feature supports Oracle ACFS replication and tagging on Solaris platforms.

For information about Oracle ACFS, refer to Introducing Oracle ACFS and Oracle ADVM .

This feature supports Oracle ACFS replication and tagging on AIX platforms.

For information about Oracle ACFS, refer to Introducing Oracle ACFS and Oracle ADVM .

This feature extends support for Oracle ACFS Security and Encryption Features on Solaris systems. Changes in functionality for Solaris environments are noted with the individual security and encryption commands.

For more information, refer to "Oracle ACFS Security" and "Oracle ACFS Encryption".

Oracle Enterprise Manager replaces Enterprise Manager Database Control for administering Oracle Automatic Storage Management Cluster File System. For more information, refer to Administering Oracle ACFS with Oracle Enterprise Manager .