RancherD is an experimental feature.

In RancherD, a server node is defined as a machine (bare-metal or virtual) running the rancherd server command. The server runs the Kubernetes API as well as Kubernetes workloads.

An agent node is defined as a machine running the rancherd agent command. They don’t run the Kubernetes API. To add nodes designated to run your apps and services, join agent nodes to your cluster.

In the RancherD installation instructions, we recommend running three server nodes in the Rancher server cluster. Agent nodes are not required.

• Certificates for the Rancher Server
• Node Taints
• Customizing the RancherD Helm Chart
• RancherD Server CLI Options
• RancherD Agent CLI Options

Certificates for the Rancher Server

Rancherd does not use cert-manger to provision certs. Instead RancherD allows you to bring your own self-signed or trusted certs by storing the .pem files in /etc/rancher/ssl/. When doing this you should also set the publicCA parameter to true in your HelmChartConfig. For more information on the HelmChartConfig, refer to the section about customizing the RancherD Helm chart.

Private key: /etc/rancher/ssl/key.pem

Certificate: /etc/rancher/ssl/cert.pem

CA Certificate(self-signed): /etc/rancher/ssl/cacerts.pem

Additional CA Certificate: /etc/ssl/certs/ca-additional.pem

Node Taints

By default, server nodes will be schedulable and thus your workloads can get launched on them. If you wish to have a dedicated control plane where no user workloads will run, you can use taints. The node-taint parameter will allow you to configure nodes with taints. Here is an example of adding a node taint to the config.yaml:

node-taint:
  - "CriticalAddonsOnly=true:NoExecute"

Customizing the RancherD Helm Chart

Rancher is launched as a Helm chart using the cluster’s Helm integration. This means that you can easily customize the application through a manifest file describing your custom parameters.

The RancherD chart provisions Rancher in a daemonset. It exposes hostport 8080/8443 down to the container port (80/443), and uses hostpath to mount certs if needed.

RancherD uses helm-controller to bootstrap the RancherD chart. To provide a customized values.yaml file, the configuration options must be passed in through the helm-controller custom resource definition.

Here is an example of the manifest:

apiVersion: helm.cattle.io/v1
kind: HelmChartConfig
metadata:
  name: rancher
  namespace: kube-system
spec:
  valuesContent: |
    publicCA: true

Put this manifest on your host in /var/lib/rancher/rke2/server/manifests before running RancherD.

Common Options

RancherD Server CLI Options

The command to run the Rancher management server is:

rancherd server [OPTIONS]

It can be run with the following options:

Config

Logging

Listener

Data

Networking

Cluster

Client

Flags

Database

System Images Registry

Components

Cloud Provider

Security

Agent Node

Agent Runtime

Agent Networking

Agent Flags

Experimental

RancherD Agent CLI Options

The following command is used to run the RancherD agent:

rancherd agent [OPTIONS]

The following options are available.

Config

Data

Logging

Cluster

Agent Node

Agent Runtime

Agent Networking

Agent Flags

System Images Registry

Cloud Provider

Security