I'm currently planning a v6 only small datacenter network.
Imagine for now one deployment consisting of 6 racks with 12 servers per rack.
Each server has 2 NICs for two physically separate networks (management & data).
The racks are interconnected.

For ULA addresses I want to divide 16 Subnet Bits with 4 bits for "network type", 4 bits for "deployment ID" and 8 bits for "rack ID". So each rack gets its own subnet and humans can identify them easily. 
So per rack I need to send RAs with the reachable on-link prefixes of the other racks and one prefix for SLAAC so the servers generate their addresses. But the racks don't have physical routers. Only the distribution layer above the racks has routers.

My idea now is to let one server send RAs with "Router Lifetime = 0" (which is allowed in that case (see RFC4861)) for the rack. But now the RAs spread over all racks.

Thesis: I need to block RAs from traversing through switches.

Question: Is this how it is meant to be done? Are there any operational experiences with datacenter networks on v6 only?