Magnum
Magnum lets you create clusters via the OpenStack APIs. To do that, you base your configuration on a Cluster Template. The template defines parameters, such as worker flavors, which describe how the cluster will be constructed. In each region, we offer predefined public Cluster Templates with ready-to-use configurations. To learn more about Cluster Templates, check out the Magnum documentation.
Once you have chosen your Cluster Template, you move on to create a cluster based on that template. When you create the cluster, you can define the number of nodes, ask for multiple masters behind a load balancer, etc.