Automatic OCR backups

Oracle CRS backs up the OCR automatically at regular intervals. The standard backup frequency and retention policies are Every 4 hours – keeping the last 3 copies. Every day (at the end) – keeping the last 2 copies. Every week (at the end) – keeping the last 2 copies.   You can find the location …

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SQL performance analyzer in Oracle 11g

SQL performance analyzer performs a similar job to the SQL Tuning Advisor with one major difference, SQL performance analyser allows you to compare the performance of SQL statements before and after a change, allowing you to predict the impact of changes to the system on SQL performance as well as pre tuning your database before …

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Where to find Oracle clusterware log files.

To make administration and problem diagnosis easier in Oracle Clusterware, there is a single consolidated directory structure for the main clusterware log files.   This is found under $GRID_HOME/log/[hostname]/   The CRSD logfile – crsd.log is stored in the /crsd/ directory and is archived every 10mb.   The CSS logfiles – cssd.log is stored in …

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How to enable Clusterware Resource Debugging in Oracle RAC

In order to enable clusterware resource debugging you need to set the resource attribute USR_ORA_DEBUG to 1 for the resource that you wish to debug. $ crsctl set log res “ora.host01.vip:1” When you are finished you issue almost the same command to disable the clusterware debugging (set USR_ORA_DEBUG to 0): $ crsctl set log res “ora.host01.vip:0” You can also use an initialization …

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How to Check the integrity of OCR files

How to Check the integrity of Oracle Cluster Configuration (OCR) files To check the health ot OcR files, ther are 3 methods that can be used in unison. Check for voting disk issues in the ocssd.log with: grep $GRID_HOME/log/[hostname]/ocssd.log There are also 2 commands that can help. They are ocrcheck and cluvfy You run ocrcheck …

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Error ORA-15260 when attempting to issue an alter diskgroup command.

The ORA-15260 error when attempting ot issue an alter diskgroup command is a permissions issue. It will generally be because you are logged in as SYSDBA rather than SYSASM. Prior to 11gR2 you could log in and administer diskgroups with SYSDBA privileges but this changed with 11.2.   SQL> ALTER DISKGROUP DATA add disk ‘/dev/oracleasm/disks/DISK2’;ALTER …

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How to Install Virtualbox Guest additions for Oracle Enterprise Linux 6

  This tutorial leads straight on from ‘How to install Oracle Enterprise Linux 6 on Virtualbox’ and assumes that you have a clean install to work from. If you haven’t installed OEL6 or have any problems with this tutorial, I recommend that you follow that tutorial before this one. So, in virtual box, Guest additions gives you some cool …

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How to install OEL6 on Virtualbox

Virtualbox is Oracle’s solution to visualization and as such it is very powerful. It is similar to VMware as it has much the same capabilities and you can run servers through it on an enterprise level. For the purposes of experimenting with operating systems and learning Oracle, it gives us some amazing benefits and makes …

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