Hi,
Which one do you prefer:
1- having a copy of data off-site by disk subsystem copy services:
2- implementing D/R with VTL-to-VTL communication

Number 1:
-needs more disk capacity
-copy services license price
-more bandwidth is needed between sites even in asynchronous mode
-more difficult LAN-free scenario if there are not many physical tape
drives. So, something like SANergy is needed

Number 2:
- VTL price in both sites
- less bandwith is needed (it is backup data, not the changing data itself.
Furthermore, it is de-duped)
- virtual tape drives make LAN-free easier to implement and operate
...

Appreciate any comments,
Mehdi