Flocker as a clustered container data volume manager

So far, we have discussed storage solutions that stored the data outside the Kubernetes cluster (except for emptyDir and HostPath, which are not persistent). Flocker is a little different. It is Docker-aware. It was designed to let Docker data volumes transfer with their container when the container is moved between nodes. You may want to use the Flocker volume plugin if you're migrating a Docker-based system that use a different orchestration platform, such as Docker compose or Mesos, to Kubernetes and you use Flocker for orchestrating storage. Personally, I feel that there is a lot of duplication between what Flocker does and what Kubernetes does to abstract storage.

Flocker has a control service and agents on each node. Its architecture is very similar to Kubernetes with its API server and the Kubelet running on each node. The Flocker control service exposes a REST API and manages the configuration of the state across the cluster. The...