Category Archives for RAC

Administering Oracle Clusterware

1. CRSCTL: Cluster Control utility performs various administrative operation of oracle clusterware. It is located in $ORA_CRS_HOME/bin and must be executed by the “root” user. a. To check the current state of all oracle clusterware daemon: [root@rac1 bin]# ./crsctl check crs CSS appears healthy CRS appears healthy EVM appears healthy b.You can also check the […]

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Voting Disk Management in RAC

What is voting disk ? Voting disk is a file that manages information about node membership. It is located on the shared cluster system or a shared raw device file. Its primary purpose is to help in a situation where the private network communication fails. CSS (Cluster Synchronization Service) is the service that determines which […]

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Single Instance to RAC conversion using DBCA :Part-II

This is Part II for Single Instance to RAC conversion. For Part-I click here Pre-requisite before conversion 1. Set up the cluster environment and validate the cluster using clvufy. 2. Copy the pre-configured database image from $OLD_ORACLE_HOME/ assistants/ dbca/ templates/ *.dbf & *.dbc    to  new rac environmnet   $NEW_ORACLE_HOME/assistants/dbca/templates/*.dbf & *.dbc 3. Run  ORACLE_HOME/bin/dbca step-1 […]

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Single Instance to RAC conversion using DBCA :Part-I

There is three method available, you can use any of them to convert single instance to RAC instance. a. using dbca b. using EM c. using rconfig utility Here we are converting using DBCA (DataBase Configuration Assistant). Conversion of single instance database to RAC database using DBCA consists of two part. In first part, we […]

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Common Wait Events in a Real Application Clusters

Difference in single instance and RAC instance: In a single database instance environment, there will be only one set of shared memory segments for the database. In other words, the buffer cache and shared pool are local to that particular instance; at any point in time the processes attached to that particular instance will be […]

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Backup and recovery of Oracle Clusterware – OCR

The backup of OCR content(Oracle Cluster Registry, to know more about OCR click here) is performed using two methods: Automatic OCR backup Manually OCR backup . 1. Automatic OCR Backup OCR is automatically backed up physically Every four hours At the end of every day At the end of every week To check current location of […]

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Oracle RAC – Clusterware Installation Overview

This post covers overview of Oracle Clusterware Installation, for step by step guide on How to install Clusterware using VMware 2.0 (including steps to configuring multiple linux machine/network card/hard disk/raw device for OCR/Voting Disk on one Windows Machine)  register for online Oracle RAC DBA training (499 USD) . Requirement for Oracle Clusterware 1. External Shared Disk to store […]

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Oracle Exadata Storage

Oracle Exadata Storage Server The HP Oracle Exadata Storage Server is a storage product highly optimized for use with the Oracle database. Exadata is a combination of software and hardware used to store and access the Oracle database. It provides database aware storage services, such as the ability to offload database processing from the database […]

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HugePages and Oracle RAC

 HugePages and Oracle RAC HugePages is a feature integrated into the Linux kernel with release 2.6. This feature basically provides the alternative to the 4K page size providing bigger pages. HugePage sizes vary from 2MB to 256MB based on kernel version and H/W architecture.  Why HugePages Should Be Used on RAC with 64-bit Linux? Very […]

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RAC Basics : CRS, Voting Disk, OCR, Cache Fusion ….

Oracle Clusterware (Cluster Ready Services in 10g/ Cluster Manager in 9i) – provides infrastructure that binds multiple nodes that then operate as single server. Clusterware monitors all components like instances and listeners. There are two important components in Oracle clusterware, Voting Disk and OCR (Oracle Cluster Registry). . Voting Disk – is file that resides […]

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