Kontena does not replace Docker. It's a management and orchestration layer on the top of Docker. With Kontena you can manage and deploy your Docker applications.

Kontena applications can be described in YAML file (kontena.yml). Kontena.yml extends docker-compose.yml format by introducing some new attributes only supported in Kontena, for example scale of a service and deploy specific attributes.

A Service definition describes the container image, networking, scaling and stateful/stateless attributes for your application. Services may be linked together to create desired architecture. Each service is automatically assigned with internal DNS address that can be used inside your application for inter-Service communications.

The summary of Kontena key features:

* Scheduler with affinity filtering

* Built-in private Docker image registry

* Remote VPN access for workload services

* Virtual Networking Built-In

* Ready made load-balancing service

* Log and statistics aggregation with streaming

* Access control and roles for Kontena users

feels like it's doing container cluster management (ala kubernetes) and provides a simple way for orchestration (like heat for openstack)