1.Take the backup of oracle inventory
Linux : cat /etc/oraInst.loc
Others : cat /etc/opt/oracle/oraInst.loc
use tar to take backup of binaries.
$tar -cvf /home/oracle/Inventory.tar /home/oracle/oraInventory
$tar -xvf /home/oracle/Inventory.tar
cvf : create verbose file
xvf : extract verbose file
2.Take the backup of oracle binaries.
3.Take the backup of oracle database.
Note : If at all if the patch set installation is failed, restore the inventory from the backup and also restore oracle binaries from the backup.
All patches that are installed using opatch can be rollbacked using opatch.
eg : 789765.zip
$opatch apply 789765
$opatch rollback 789765
$opatch napply <p1> <p2>
Before installing a patch/patch set, go through the "readme" file.
