Once the core Kubernetes cluster components are up and running, KET installs additional components that are required to produce a fully operational cluster. These extra components are collectively referred to as add-ons, and they include the networking plugin, cluster DNS, heapster monitoring, and others.
Add-on installation and configuration can be controlled via the plan file under
the add-ons section. KET supports the following add-ons:
The Container Networking Interface (CNI) enables the use of different networking solutions with a Kubernetes cluster. KET supports various CNI providers, enabling you to choose the most appropriate for your environment.
Plan file options:
| Field | Description |
|---|---|
add_ons.cni.disable |
Set to true to disable the installation of CNI |
add_ons.cni.provider |
Choose the CNI provider. Options: calico, weave, contiv, custom |
add_ons.cni.options.calico.mode |
The Calico networking mode. Options: bridged, routed |
When CNI is disabled, KET will skip the installation of the CNI binaries and CNI plugin. Furthermore, KET will also skip the cluster smoke test, as it will fail without a working pod network.
If the providers supported by KET do not fit your needs, you may bring your own
CNI-compliant provider by setting the CNI provider to custom in the plan file.
In this configuration, KET will skip the cluster smoke test, as it will fail without a working pod network.
DNS provides service discovery to pods running on the cluster. KET deploys KubeDNS as the DNS service on the cluster.
Plan file options:
| Field | Description |
|---|---|
add_ons.dns.disable |
Set to true to disable the installation of KubeDNS in the cluster |
Heapster is a monitoring solution that enables container monitoring throughout
the cluster. When heapster is running on the cluster, kubectl and the Kubernetes
dashboard surface resource utilization metrics for all pods.
Important: If you wish to persist the gathered metrics, you must set the add_ons.heapster.options.influxdb.pvc_name option.
Plan file options:
| Field | Description |
|---|---|
add_ons.heapster.disable |
Set to true if heapster should not be deployed during installation |
add_ons.heapster.options.heapster.replicas |
Number of replicas for the heapster deployment |
add_ons.heapster.options.heapster.serviceType |
Set the service type for the Heapster service |
add_ons.heapster.options.heapster.sink |
The location where Heapster will store it's data |
add_ons.heapster.options.influxdb.pvc_name |
Name of a persistent volume claim that will be used by the influxdb databse for persistence. This PVC must be manually created after installation. |
The Kubernetes dashboard is a web-based UI for managing Kubernetes clusters.
Plan file options:
| Field | Description |
|---|---|
add_ons.dashboard.disable |
Set to true to skip the deployment of the Dashboard |
Helm is the official package manager for Kubernetes. KET includes the helm client-side binary in the distribution package. KET also installs the server-side agent, Tiller, on the cluster during installation.
Plan file options:
| Field | Description |
|---|---|
add_ons.package_manager.disable |
Set to true if the package manager should not be deployed during installation |
add_ons.package_manager.provider |
The package manager that should be deployed. Options: helm |