A clustering tool is software that allows an operator to talk to a single end point and to command and orchestrate a set of resources, in our case containers. Instead of manually distributing workloads (containers) on a cluster, a clustering tool is used to automate this and many other tasks. It's the clustering tool that will decide where to start jobs (containers), how to store them, when to eventually restart them, and so on. The operator needs to only configure some behaviors, decide the cluster topology and size, tune settings, and enable or disable advanced features. Docker Swarm is an example of clustering tool for containers.

Beyond clustering tools, there is also a choice of container manager platforms. They do not provide container hosting, but interact with one or more existing systems; this kind of software usually offer good web interfaces, monitoring tools, and other visual or higher-level functionalities. Examples of container manager platforms are Rancher or Tutum (acquired in 2015 by Docker Inc.).