From star history:
| PAAS | Ideal use case |
|---|---|
| Dokku | Hobby Projects / Prototypes that are not mission critical |
| Flynn | Small Production Deployments |
| Kubernetes | Huge Deployments and Mission Critical |
| Deis | Need a friendlier workflow on top of Kubernetes |
| Spinnaker | Multi-cloud, large enterprise |
From This stackoverflow
Kubernetes is really three things:
- A way to dynamically schedule containers (actually, sets of containers called pods) to a cluster of machines.
- Manage and horizontally scale a lot of those pods using labels and helpers (ReplicationController)
- Communicate between sets of pods via services, expose a set of pods externally on a public IP and easily consume external services. This is necessary to deal with the horizontal scaling and the dynamic nature of how pods get placed/scheduled.
This is all very much a tool set for managing compute across a set of machines. It isn't a full application PaaS. Kubernetes doesn't have any idea what an "application" is. Generally PaaS systems provide an easy way to take code and get it deployed and managed as an application. In fact, I expect to see specialized PaaS systems built on top of Kubernetes -- that is what RedHat OpenShift is doing.
One way to think about Kubernetes is as a system for "logical" infrastructure (vs. traditional VM cloud systems)
- Places containers on nodes
- Recovers automatically from failure
- Basic monitoring, logging, health checking
- Enables containers to find each other.
| Number | Name | Examples |
|---|---|---|
| Layer 8 | PAAS (Workflow) | Deis, Flynn, Rancher, OpenShift |
| Layer 7 | Orchestration | Spinnaker |
| Layer 6 | Container Management | Swarm, Kubernetes, Marathon |
| Layer 5 | Scheduling | Mesos, Omega |
| Layer 4 | Container Engine | Docker, Rocket, OSv |
| Layer 3 | Operating System | Ubuntu, RHEL, CoreOS |
| Layer 2 | Virtual Infrastructure | vSphere, EC2 |
| Layer 1 | Physical Infrastructure | Raw Compute, Network, Storage |
Rancher: Comparing Orchestration Engine Options
Comparison of mult-host Docker networking: Weave Flannel Calico
