Here I share my experience in upgrdaing Symantec Opscenter 7.1 to 7.6
Step1: Take backup of Ops DB using symantec recommended command. ( Please refer below link for the same. Taking backup is only to meet any unforeseen condition.While upgrdaing itself backup will be taken and placed in the same server in below location.C:\Program Files\Symantec\OpsCenter_SavedData )
Step 2: Ensure the compatability of the Sym Ops ( 7.6 ) with the OS Version ad Bit.
Step 3: Copy the Netbackup Opscenter 7.6 installation file to the OS and Proceed with Installation. If the Netbackup 7.1 is already installed, the installation will identify the older version and update the NBOPS to new version without affecting the DB. Please find the screenshot.