Homelab

I'm planning on upgrading my r720xd's changing the quad 1gb port card for a quad 2x 10gb, 2x 1gb card. I'm trying to conceptualize how this work as I'm still new to home networking. I have a 48 port 1gb switch and will be getting a 10gb sfp+ switch.

The 10gb switch will use an rj45 to connect to the main switch. And the four servers will connect to the 10gb switch via sfp+.

How do I use the 1gb ports on the dtr card? Do they run at the same time to the primary switch? Are they used only as fail over? If so does that mean that most of the traffic, that's not between the servers themselves, will go through the primary switch at 1gb speeds?

I'm trying to figure out how to make sure that the high bandwidth traffic goes through the sfp+ ports and not through the 1gb ports when the 1gb ports are in use.