I was facing the same challenge. How to dynamically add the correct number of hard disks to the command line for recovery when I didn't know the number of hard disks?

I implemented a scripted solution to log the number of hard disks at the time of adding the VM to NetWorker, as well as quering Virtual Center when doing a recovery test. Usually, the number of hard disks don't change that often and one of these numbers should be correct.