Ok so all you want to do is a backup involving SnapVault?
If so then yes snapvault relationship needs to exists, meaning secondary volume, etc
In SC you have two choices do a snapvault update in which case we
1. create snapshot on primary
2. perform snapvault transfer (or PM can do transfer if you are using PM)
3. wait for transfer
4. create snapshot on seconday volume (or PM will do that if it is doing transfer)
In addition you can also use snapvault scheduler on storage system. SC will:
1. create a snapvault scheduler compliant snapshot on primary
2. wait for snapshot creation process
3. scheduler on storage system is responsible for transferring
There are about 30 videos under content on SC communities page which show how to setup snapvault, proteciton manager, etc, I recommend watching them.