Oracle 11g Release 2, New Features for DBA

1) Cluster can be seen everywhere

In previous versions, Oracle Clusterware must be installed independently in its own in the ORACLE HOME, and can only be used in the RAC environment, all in the Oracle 11g R2 thoroughly subversive, because in this version support the installation of Oracle Net grid infrastructure, and only need a separate ORACLE HOME, which includes the Oracle Clusterware and Oracle Automatic Storage Management (ASM). Through the upgraded Oracle Universal Installer is installed on a grid infrastructure.

Single-instance RAC (Oracle restart):- Oracle 11g R2 extends the Oracle Clusterware features provided for any single instance high availability features, is essentially a single-instance database into a RAC database. Oracle 11g R2 features to help restart the Oracle Grid Infrastructure Oracle high availability service control server, which a listener when you restart, ASM instance and database should be started, it completely replaced the previous DBA often used DBSTART script. Similarly, when a single database instance crashes or other abnormal termination, Oracle restart feature will automatically monitor the instances of failure and automatically restart it, just like in a real environment, the same as RAC.

SRVCTL Upgrade:- If you manage an old version of the RAC environment, you may already be familiar with the RAC environment maintenance tools SRVCTL, in the 11g R2, this tool has been expanded, and now can manage single-instance RAC, as well as the listener and the ASM instance .

Cluster time synchronization services:- Oracle 11g R2 on all RAC nodes now need to configure the time synchronization, if you have the experience of being expelled from a node RAC cluster configuration, you must know how much more difficult, especially the two server's time is not synchronization and time stamp log files is not synchronized, Oracle versions prior to using the system provides Network Time Protocol (NTP) synchronization of all nodes in time, but need to connect to the Internet standard time servers, NTP, as a replacement for, Oracle 11g R2 provides a new cluster time synchronization services to ensure that all nodes in the cluster of the time consistent.

Grid Plug and Play:- In previous versions, configure the most complex part of the RAC is to determine and set all the nodes need to use a public ip address, private ip address and virtual ip address. To simplify the RAC installation, Oracle 11g R2 provides a new grid Name Service (GNS), and domain name servers which collaborate to deal with each grid component ip address allocation, when the cluster environment across multiple databases in this new features extremely useful.

Cleanly uninstall the RAC components: If you've ever tried to delete multiple nodes all RAC traces, it would certainly love to this new feature, the Oracle 11g R2, all installation and configuration assistants, in particular, Oracle Universal Installer (OUI), Database Configuration Assistant (DBCA) and Network Configuration Assistant (NETCA), have been enhanced, when the need to uninstall the RAC components, we can ensure that dumping was clean.

2) ASM joined the cluster

Oracle 11g R2 ASM filled with a number of attractive new features, for beginners, ASM, and Oracle 11g R2 Clusterware is installed on the same Oracle Home, it is therefore recommended before eliminating redundant Oracle Home installation method, and from ASM DBCA was spun off, and have a dedicated Automatic Storage Management Configuration Assistant (ASMCA).  The most interesting new features of ASM are:-

Intelligent data layout:- In the previous version, you want to configure ASM disk storage administrators may be required to participate, you need to configure the disk I / O subsystem, Oracle 11g R2 provides the ASM allocation unit, you can directly benefit from the disk outer edge of the cylinder get faster, can be data files, redo log files and control on the outer edge of the disk for better performance.

EM Support Workbench Extension:- In this version of the Oracle 11g R2 introduced into the enterprise management console, the automatic diagnostic repository (ADR) was expanded to include support for ASM diagnostics, package all diagnostic information directly to Oracle technical support in order to obtain ASM performance problems faster solution.

ASMCMD Enhanced:- Automatic Storage Management command-line utility (ASMCMD) also received a number of enhancements, including:-

1) Start and stop the ASM instance.

2) Backup, restore and maintain the ASM instance server parameter file (spfile).

3) The utility iostat monitor ASM disk group performance.

4) The maintenance of the new ASM cluster file system (ACFS) in the disk volume, directory and file storage. 

3) ACFS - A robust cluster file systems

Oracle also released before the off cluster file system (OCFS), later released an enhanced version of OCFS2, it allows Oracle RAC instances can share the memory read and write database files, redo log files and control files.

In addition, OCFS also allows the RAC database, Oracle Cluster registration documents (OCR) and voting disk is stored in the cluster file system, in the Oracle 10g R2, this demand has been canceled, OCR and voting disk files can be stored in the bare device or bare block device, if you have the original equipment is lost all copies of these documents, you must understand how to restore them cumbersome and, therefore, in the Oracle 11g R2, you will no longer support these files are stored on the bare device.

In order to improve the viability of these critical files, Oracle 11g R2 formally introduced a new cluster file system, called the ASM cluster file system (ACFS), in the RAC environment, ACFS documents for OCR and voting disk to provide better protection, which allows OCR to create five copies, before the cluster file system allows only two OCR save the file, a primary OCR, a mirrored OCR, but the ACFS not suitable for a separate RAC environment, in addition, almost all the operating system and data-related documents are available from ACFS's security and file sharing features to benefit.

Dynamic Volume Manager:- Oracle 11g R2 provides a new ASM Dynamic Volume Manager (ADVM) to configure and maintain stored in the ACFS file system files, using ASM disk group ADVM can build a ADVM volume within the device, manage Store the ADVM volume device files, as well as on-demand adjustment ADVM volume device space, the most important, because ADVM is built on the ASM file system architecture, and can ensure the volume stored in these files are well protected, does not appear accidental loss, because of the ASM provides a similar RAID disk array functions.

File access control:- the use of traditional Windows-style access control list (ACL) or Unix / Linux under the user / group / other access to the style ACFS directory and file to give read, write, and execute permissions, you can graphically oriented enterprise management and the command-line program ASMCMD management ACFS directory and file security.

The file system snapshots (FSS):- Oracle 11g R2, through its file system snapshots (FSS) function can be the implementation of ACFS file system snapshot, a snapshot is selected ACFS a read-only copy of the file system on the same ACFS It will automatically keep a snapshot of 63 independent ACFS, when a file is inadvertently ACFS update, delete, or other hazardous operations, this feature is very useful, using 11g R2 Enterprise Manager console or ACFS acfsutil command-line tool can find out the file and execute the appropriate version of the resume.

4) Improved Software Installation and Patching Process

Cluster Verify Utility Integration:- From Oracle 10g introduced the cluster verification utility (CVU), has now been fully integrated into the Oracle Universal Installer (OUI), and other configuration assistants (for example, DBCA).

Zero downtime patch cluster:- When the patch for the Oracle cluster, when, Oracle 11g R2 in an inappropriate place apply the patch to upgrade, which means that there will be two Oracle Home, in which a patch designed to store, but the time only can activate an Oracle Home, in the Oracle 11g R2 upgrade in no longer close down all Oracle cluster, and to achieve true zero downtime patch.

5) DBMS_SCHEDULER Upgrade

Ancient DBMS_SCHEDULER package has been thoroughly updated, DBA often use this package to schedule jobs.

File Monitor:- previous versions can not be detected in the batch process the majority of trigger events, such as the detection of a file arrived in a directory, in the Oracle 11g R2, the use of the new file monitor can ease this problem, once the document is expected to arrive in directory, DBMS_SCHEDULER can now be detected, and the new object type SCHEDULER_FILEWATCHER_RESULT register its arrival, its adoption of the new CREATE_FILE_WATCHER stored procedure to send a signal to trigger the operation DBMS_SCHEDULER.

Built-in email notifications: Whenever, DBMS_SCHEDULER scheduled tasks to start, failed, or completed, the task state can be immediately sent via email, although in previous versions can also achieve this functionality, but either call DBMS_MAIL stored procedure, or Call DBMS_SMTP stored procedure, and now this feature into DBMS_SCHEDULER in the.

Remote Operation:- DBMS_SCHEDULER now allows DBA to create the remote database and scheduling jobs.

Multi-operating objectives:- Finally, can now be multiple database instances at the same time scheduling DBMS_SCHEDULER the task, and in the RAC environment, this feature is very useful because I can use multiple database instances will be long-running task is divided into several parts, in different the database instance to perform smaller tasks.