WD Live duo

My Internet connection will be offline for the next month so meantime  I want to hardwire Mylivebookduo 6TB direct to my iMAC and use it as I would an external hard drive

Is it just a simple case of connecting the ethernet cable to the back of my iMAC or should I be changing any settings etc?

No need to change anything.   Just leave everything the way it is.

Your router will still do what it does, it just won’t have internet access.

Even if you do connect it directly, it’s still going to work like a NAS, and not be usable “as [you] would an external harddrive.”

Many thanks for your reply. I’ll leave it ‘as is’ t.hen