adding more storage is not a current feature.
It is a future feature. Verizon's next software release will enable ONLY the Esata port on the back of your DVR.
Verizon offers two dvr's currently, the 6416 would have be swapped out as it does not have such a port.
the 7216 has that port.
once that port is enabled you will be able to add upto 1 tb of data.
Cust are currently getting on a list to be offered this when it becomes available.
to get on that list - sign up at www.veirzon.com/fiostvcentral
once you are signed in, cut and paste this address in, and you will go to the sign up page. you can only access that page after you sign in. It will allow you to get on the waiting list.