Main steps :

Grid :-

1.  Check all services are up and running from 10gR2 GRID_HOME

2.  Perform backup of OCR, voting disk and Database.

3.  Create a new directory for installing 11C software on both RAC nodes.

4.  Run “runcluvfy.sh” to verify errors .

5.  Install and upgrade GRID from 10gR2 to 11cR1

6. Verify upgrade version

Check GRID Infrastructure software version and Clusterware status:

cd /oracle/grid/10.2.0/bin

bash-3.2$ ./crsctl query crs activeversion

CRS active version on the cluster is [10.2.0.5.0]

bash-3.2$ ./crsctl check crs

CSS appears healthy

CRS appears healthy

EVM appears healthy

bash-3.2$ ./crs_stat -t

Check Database status and configuration :

bash-3.2$ ./srvctl status database -d PROD

Instance PROD1 is running on node racnode1

Instance PROD2 is running on node racnode2

bash-3.2$ ./srvctl config database -d PROD

racnode1 PROD1 /export/home/oracle/db

racnode2 PROD2 /export/home/oracle/db

Perform local backup of OCR 

mkdir -p /u01/ocrbkp

[root@racpb1 ~]# cd /u01/app/11.2.0/grid/bin/

[root@racpb1 bin]# ./ocrconfig -export /u01/ocrbkp/ocrfile

Move the 11c GRID Software to the server and unzip the software : 

Run cluvfy utility to pre-check  any errors :

./runcluvfy.sh stage -pre crsinst -upgrade -rolling -src_crshome /u01/app/11.2.0/grid -dest_crshome/export/home/oracle/crs_12.1.0 -dest_version 12.1.0.1.0 -verbose

Stop the running 10g database :

./srvctl stop database -d PROD

./srvctl status database -d PROD

Instance PROD1 is not running on node racnode1

Instance PROD2 is not running on node racnode2

Take GRID_HOME backup on both nodes :

Check Clusterware services status before upgrade :

./crsctl check crs

CSS appears healthy

CRS appears healthy

EVM appears healthy

Upgrade 10g by executing runInstaller :

/export/home/oracle/grid

./runInstaller

cd /export/home/oracle/crs/bin

./srvctl status asm -n racnode1

ASM instance +ASM1 is running on node racnode1.

./srvctl status asm -n racnode2

ASM instance +ASM2 is running on node racnode2.

 ./srvctl stop asm -n racnode1

./srvctl stop asm -n racnode2

./srvctl status asm -n racnode2

ASM instance +ASM2 is not running on node racnode2.

./srvctl status asm -n racnode1

ASM instance +ASM1 is not running on node racnode1.

After running rootupgrade.sh script,Click the OK button.