Data center connectivity passing through two other sites

Hi all,

I have two data centers that I need to pass traffic between. There are two more data centers in-between these two sites that are basically acting as cross-connect facilities, but there are switches at every site. All fiber links are touching a switch at each site. Let’s say my locations are called: A-B-C-D.

My question:

Is best practice to have all switches routing to one another (each switch will route to the next switch’s SVI)? Meaning there would be SVI’s setup on each and every switch?

Or is it acceptable to have switches B and C simply passing the traffic straight through at layer 2- Trunks between all switches, SVI’s would only be setup on switch A and switch D. B and C would just be passing that traffic straight though on a dedicated VLAN.

Thanks!