1) Mount BOTH Network drives on to "client" computer -- the one you are logged on to.
2) either use Windows explorer (slow and can be problematic with large volumes of data) or any backup program to copy data from one volume (or Disk) to the other one.
3) job done.
Note if you want to copy the WHOLE network drive as an image you will need permission to access the WHOLE drive -- then you can image it with any decent backup program. Usually on a Network drive you want to copy DATA that's on it rather than the whole drive.
As I keep saying in these forums I'd invest in a decent backup program --doesn't cost much - especially compared with the cost of re-creating music / film / multi-media libraries again as well as saving critical documents / data.
Even if you use "torrents" just imagine the TIME taken to re-download all that stuff which might no longer be available --for example the original seeders might have gone.
cheers
jimbo
My Computer
At a glance
Linux CENTOS 7 / various Windows OS'es and se...Intel i7 Intel i58GB, 16GBOn Motherboard
Computer type
PC/Desktop
Computer Manufacturer/Model Number
Custom built, several laptops HP/ASUS
OS
Linux CENTOS 7 / various Windows OS'es and servers