How to define that multiple groups must be allocated on the same datacenter

The usecase I’m struggling with is that I have two datacenters a and b, each of the datacenters got both windows and linux clients.

I want to run multiple jobs where each of them contains 2 groups, one that must be allocated on the windows server and other that must be allocated on the linux server. Each group has count = 1.

The challenge is that I want to make sure that both groups in one job will be allocated in the same datacenter and I want to let Nomad decide on which datacenter allocations will be placed.

How to configure such collocation within one job? Ideally I want to use it with spread scheduler algorithm.