Mirantis OpenStack for Kubernetes (MOSK) cluster networking is complex and defined by the security requirements and performance considerations. It is based on the Kubernetes cluster networking provided by Mirantis Container Cloud and expanded to facilitate the demands of the OpenStack virtualization platform.
A Container Cloud Kubernetes cluster provides a platform for MOSK and is considered a part of its control plane. All networks that serve Kubernetes and related traffic are considered control plane networks. The Kubernetes cluster networking is typically focused on connecting pods of different nodes as well as exposing the Kubernetes API and services running in pods into an external network.
The OpenStack networking connects virtual machines to each other and the outside world. Most of the OpenStack-related networks are considered a part of the data plane in an OpenStack cluster. Ceph networks are considered data plane networks for the purpose of this reference architecture.
When planning your OpenStack environment, consider the types of traffic that your workloads generate and design your network accordingly. If you anticipate that certain types of traffic, such as storage replication, will likely consume a significant amount of network bandwidth, you may want to move that traffic to a dedicated network interface to avoid performance degradation.
The following diagram provides a simplified overview of the underlay networking in a MOSK environment: