Source Environment Details: 

ORACLE_HOME=/home/oracle/oracle/product/10.2.0/db 
CRS_HOME=/home/oracle/oracle/product/10.2.0/crs 

Oracle Database Version 

SQL> select * from v$version;

BANNER

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Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Prod

PL/SQL Release 10.2.0.1.0 - Production

CORE    10.2.0.1.0      Production

TNS for Solaris: Version 10.2.0.1.0 - Production

NLSRTL Version 10.2.0.1.0 – Production 

CRS Active Version 
crsctl query crs activeversion

CRS active version on the cluster is [10.2.0.1.0]

Note: The active version is the lowest software version running in a cluster.

CRS Software Version 
crsctl query crs softwareversion

CRS software version on node [rac1] is [10.2.0.1.0] 

Note: The software version is the binary version of the software on a particular cluster node. 

Task 1 

Perform Clean shutdown to the database in All node 

Shutdown ASM services on All Node

RAC1----> ./srvctl stop nodeapps -n RAC1

RAC2-------> ./srvctl stop nodeapps -n  RAC2

Shutdown CRS Service on All Node  

./crsctl stop crs 


Task 2
Navigate to patch set 4 (8202632) on node 1 
Launch Oracle Universal Installer 
On the destination page select Oracle CRS Home 
Click Next………………………..(Must be Complete Post Installation Steps) 

Task 3 Down the Listener Service
$srvctl stop listener -n RAC1
$srvctl stop listener -n RAC2 

Task 4   
Navigate to patch set 4 (8202632) on node 1 
Launch Oracle Universal Installer
On the destination page select Oracle Database Home 
Click Next………………………..(Must be Complete Post Installation Steps) 

Task 5
Start CRS Stack on Node 1 

$./crsctl start crs 

Task 7 Connect Node 1 

 $ sqlplus /nolog

SQL> CONNECT SYS AS SYSDBA

SQL> STARTUP NOMOUNT

Set the CLUSTER_DATABASE initialization parameter to FALSE:

SQL> ALTER SYSTEM SET CLUSTER_DATABASE=FALSE SCOPE=spfile;

Shut down the database:

SQL> SHUTDOWN

Enter the following SQL*Plus commands:

SQL> STARTUP UPGRADE

SQL> SPOOL patch.log

SQL> @?/rdbms/admin/catupgrd.sql

SQL> SPOOL OFF

Restart the database:

SQL> SHUTDOWN IMMEDIATE

SQL> STARTUP

SQL> @?/rdbms/admin/utlrp.sql

Set the CLUSTER_DATABASE initialization parameter to TRUE:

SQL> ALTER SYSTEM SET CLUSTER_DATABASE=TRUE SCOPE=spfile; 

Restart the database:

SQL> SHUTDOWN IMMEDIATE

SQL> STARTUP

Start any database services that you want to use:

$ srvctl start service -d db_name -s service_name