Introduction of Opatch and how to apply

Introduction to Opatch

Opatch is Oracle supplied utility .

OPatch is used for patching Oracle software. 

OPatch is a java based utility that allow the application and rolling back of interim patches to an Oracle 

product

The program has sub-commands that may take arguments.

 Getting and using Opatch utility

OPatch is PLATFORM specific.

Release is based on Oracle Universal Installer version

The latest opatch utility can be downloaded via patch number 6880880 from My Oracle Support .

Downloaded Patch to be unzipped in OH , which will create a directory $ORACLE_HOME/Opatch

Execute the following command  to verify the version

        $ORACLE_HOME/Opatch/opatch version

 Main functionality of Opatch    

Applying the patch 

Rollback the patch 

Conflict check 

Report the installed components and patches

 Set PATH environment variable

Windows: set PATH=%ORACLE_HOME%/OPatch:%PATH%

Unix: export PATH=$ORACLE_HOME/OPatch:$PATH

 Opatch prerequisite checks

Check ORACLE_HOME  environment variable

Check for JRE / JDK

Check for Oracle Universal Installer and OPatch Version Compatibility

Checks for PERL( specific to 9i/10gR1 )

Check for Patch Applicable on Operating System

Check for System Space

Check for System Commands, which are used for system updates    e.g. fuser , ar , ld …etc..

Architecture of Inventories

Inventory Pointer file

Default Location : /etc/oraInst.loc or /var/opt/oracle/oraInst.loc ( for most UNIX systems )

Gives the location of central inventory

Central Inventory

Location given by Inventory pointer file.

As per OFA architecture, $ORACLE_BASE/oraInventory

Critical File : - <central-inventory>/ContentsXML/inventory.xml

Provides information about Oracle installations present on system

On Windows : C:\Program Files\Oracle\Inventory

Local Inventory( Oracle Home inventory )

Location : $ORACLE_HOME/inventory

Critical File : - $ORACLE_HOME/inventory/ContentsXML/comps.xml

Contains list of installed components/interim patches in this particular Oracle Home 

Environment variables used by OPatch

ORACLE_HOME : This variable must point to a valid Oracle Home and matches the value when that 

Oracle Home was installed.

OPATCH_DEBUG: Setting this variable to "true" sets the log level to debug.

OPATCH_PLATFORM_ID : If this variable to set to some numeric value, then OPatch skips platform ID 

check and assumes the platform ID to be the one specified here.

OPATCH_NO_FUSER: Setting this variable to "true" informs the OPatch to skip the check for active 

executables.

PATH: This variable must have a valid Opatch utility location included in it. 

Most common commands available with OPatch

$ 'opatch apply ...' is to apply a patch

$ 'opatch rollback ...' is to roll back a patch

$ 'opatch lsinventory' is to show inventory on an Oracle Home

$ 'opatch query ...' is to query a given patch from specific details

$ 'opatch version' is to show the version of the OPatch being used

$ 'opatch prereq ...' is to invoke some prerequiste checks

$ 'opatch util ...' is to invoke some independent utilities 

Opatch –help

Opatch -help command  : Invoking OPatch without arguments or with the 'help' sub-command returns 

the list of valid sub-commands to the user:

Usage: opatch [ -help ] [ -r[eport] ] [ command ]

opatch –help apply

opatch –help lsinventory

opatch –help nappl

opatch –help nrollback

opatch –help rollback

opatch –help query

opatch –help version

opatch –help prereq

opatch –help util