VLAN's are new for me so I'm sorry if this is a dumb question.
We are implementing a VLAN and I will need to be able to backup servers on
both sides. There will be a router in between however, I am hesitant to
pull backup traffic accross the router because of bandwith.

What is the best way to do this? Should I just pull it across the router
anyway? Can I dual NIC the backup server?

Any advice?