The guides are point in time contributions, and may not always be up to date with the latest work in devstack.
Walk through various setups used by stackers
Building a DevStack cluster with Neutron Networking. This guide is meant for building lab environments with a dedicated control node and multiple compute nodes.
Procedure to setup DevStack with KVM-based Nested Virtualization. With this setup, Nova instances will be more performant than with plain QEMU emulation.