Fleet
Fleet is a cluster manager/scheduler that controls service creation at the CoreOS cluster level. We can think of Fleet as Systemd for the cluster. For an overview of Fleet, refer to Chapter 1, CoreOS Overview. Fleet is used mainly for the orchestration of critical system services, while other orchestration solutions such as Kubernetes are used for application service orchestration. Fleet is not under active development and is mostly under the maintenance mode.
Installation
Fleet is installed and started by default in CoreOS. The following is the Fleet version in the CoreOS stable 766.3.0 release:

Fleet can also be installed in a standalone Linux ...
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