Question about Cisco Nexus vPC domain IDs

Hello

​

We have a Nexus core pair in vPC Domain 1 and will be adding multiple pairs of downstream Nexus access switches. I know that the vPC Domain ID needs to be different for the downstream pairs but do the downstream pairs also need to be in different Domain IDs to each other? For example should we put one pair in vPC Domain 2, another pair in vPC Domain 3....etc, or can we put all of the pairs in vPC Domain 2? We're planning on setting up double-sided vPC topology between the core pair and the access switch pairs so all four links in a connection will be in a single vPC and port-channel ID.

​

Thanks

AK