Comparison with Commercial Solutions

As metal-stack is the foundation to build Kubernetes clusters on premise on bare metal, there are several commercial solutions available which offer management of Kubernetes. In this document we describe the differences between some of the most popular solutions. It´s is not a complete list.

Comparison between Gardener on Metal Stack and Openshift running on VMWare.


Gardener is a Kubernetes cluster manager to organize a fleet of Kubernetes clusters at scale. It is designed to scale to thousands of clusters at a variety of IaaS Providers regardless where - in the cloud or on premise, virtualized or bare metal. It not only manages the creation and deletion of Kubernetes clusters, it also takes care of updating or upgrading Kubernetes and the operating system of the involved worker nodes in a automatic manner. Gardener is designed cloud-native and as such, it defines clusters, workers and all other components as Kubernetes resources (like pods and deployments) and reconciles these resources to the desired state.


Kubernetes is the de facto open-source standard for container scheduling and orchestration in the data center.


A fork of Kubernetes with proprietary addons, created by RedHat. For all details see:


Is an IaaS provider for bare metal focused to create Kubernetes cluster on premise. Gardener support is built in.


The most used virtualization technology in the enterprise data centers.

Comparison of Gardener on Metal Stack vs. Openshift on VMWare

FeatureGardener on Metal StackOpenshift on VMWare
Container Runtimedocker, containerd, gvisorcri-o
Host Operating SystemUbuntu, Debian , also see OSRHEL, Fedora-Core
Network PluginsCalico, Cilium(soon)Openshift SDN
StorageLocal NVME, Lightbits NVMEoTCP, all CSI compatible Solutions, also see StorageCSI compatible
LoadbalancingBGP built inrequires extra HW like F5, VMWare NSX
IO at Native SpeedPods run on bare metalall IO must go through the Hypervisor
Hard MultitenancyWorkers, firewall and load balancers are dedicated for every cluster on bare metalShared virtualization hosts, shared load balancers
UIGardener DashboardOpenshift Console
Multi-cluster managementYes (through Gardener)Requires extra licences SW: Redhat Advanced Cluster Manager
Automatic Kubernetes UpdatesYesYes
Automatic Worker Nodes UpdatesYesYes
Supported IaaS ProvidersGCP, AWS, Azure, Alibaba, Openstack, VMWare, metal-stack and moreGCP, AWS, Azure Openstack, VMWare
Monitoring / Logging StackGrafana/Loki, Kibana/ElasticKibana/Elastic
GitOPSTool of choice via Helm InstallOpenshift GitOPS
Container Registryall public accessible registries, private deployed registry of choiceall public accessible registries, in cluster registry
CI/CDTool of choice via Helm InstallJenkins
SecurityK8s control plane isolated from tenant, PSP enabled by defaultStrong cluster defaults
CNCF Kubernetes certifiedYes (Gardener)Yes
Local developmentminikube, kindminishift
Proprietary extensionsNoDeploymentConfig and others
kubectl accessYesYes