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Deploying Autonomous Shoot Clusters Locally

Caution

The gardenadm tool is currently under development and considered highly experimental. Do not use it in production environments. Read more about it in GEP-28.

This document walks you through deploying Autonomous Shoot Clusters using gardenadm on your local machine. This setup can be used for trying out and developing gardenadm locally without additional infrastructure. The setup is also used for running e2e tests for gardenadm in CI (Prow).

If you encounter difficulties, please open an issue so that we can make this process easier.

Overview

gardenadm is a command line tool for bootstrapping Kubernetes clusters called “Autonomous Shoot Clusters”. Read the gardenadm documentation for more details on its concepts.

In this guide, we will start a KinD cluster which hosts pods serving as machines for the autonomous shoot cluster – just as for shoot clusters of provider-local. The setup supports both the high-touch and medium-touch scenario of gardenadm.

Based on Skaffold, the container images for all required components will be built and deployed into the cluster. This also includes the gardenadm CLI, which is installed on the machine pods by pulling the container image and extracting the binary.

Prerequisites

• Make sure that you have followed the Local Setup guide up until the Get the sources step.
• Make sure your Docker daemon is up-to-date, up and running and has enough resources (at least 8 CPUs and 8Gi memory; see here how to configure the resources for Docker for Mac).

  Additionally, please configure at least 120Gi of disk size for the Docker daemon.

Tip

You can clean up unused data with docker system df and docker system prune -a.

Setting Up the KinD Cluster

make kind-up

Please see this documentation section for more details.

All following steps assume that you are using the kubeconfig for this KinD cluster:

export KUBECONFIG=$PWD/example/gardener-local/kind/local/kubeconfig

High-Touch Scenario

Use the following command to prepare the gardenadm high-touch scenario:

make gardenadm-high-touch-up

This will first build the needed images, deploy 2 machine pods using the gardener-extension-provider-local-node image, install the gardenadm binary on both of them, and copy the needed manifests to the /gardenadm/resources directory.

Afterward, you can use kubectl exec to execute gardenadm commands on the machines.

Let’s start with exec’ing into the machine-0 pod:

$ kubectl -n gardenadm-high-touch exec -it machine-0 -- bash
root@machine-0:/# gardenadm -h
gardenadm bootstraps and manages autonomous shoot clusters in the Gardener project.
...

root@machine-0:/# cat /gardenadm/resources/manifests.yaml
apiVersion: core.gardener.cloud/v1beta1
kind: CloudProfile
metadata:
  name: local
...

Bootstrapping a Single-Node Control Plane

Use gardenadm init to bootstrap the first control plane node using the provided manifests:

root@machine-0:/# gardenadm init -d /gardenadm/resources
...
Your Shoot cluster control-plane has initialized successfully!
...

Connecting to the Autonomous Shoot Cluster

The machine pod’s shell environment is configured for easily connecting to the autonomous shoot cluster. Just execute kubectl within a bash shell in the machine pod:

$ kubectl -n gardenadm-high-touch exec -it machine-0 -- bash
root@machine-0:/# kubectl get node
NAME        STATUS   ROLES    AGE     VERSION
machine-0   Ready    <none>   4m11s   v1.32.0

You can also copy the kubeconfig to your local machine and use a port-forward to connect to the cluster’s API server:

$ kubectl -n gardenadm-high-touch exec -it machine-0 -- cat /etc/kubernetes/admin.conf | sed 's/api.root.garden.internal.gardenadm.local/localhost:6443/' > /tmp/shoot--garden--root.conf
$ kubectl -n gardenadm-high-touch port-forward pod/machine-0 6443:443

# in a new terminal
$ export KUBECONFIG=/tmp/shoot--garden--root.conf
$ kubectl get no
NAME        STATUS   ROLES    AGE   VERSION
machine-0   Ready    <none>   10m   v1.32.0

Joining a Worker Node

If you would like to join a worker node to the cluster, generate a bootstrap token and the corresponding gardenadm join command on machine-0 (the control plane node). Then exec into the machine-1 pod to run the command:

root@machine-0:/# gardenadm token create --print-join-command
# now copy the output, terminate the exec session and start a new one for machine-1

$ kubectl -n gardenadm-high-touch exec -it machine-1 -- bash
# paste the copied 'gardenadm join' command here and execute it
root@machine-1:/# gardenadm join ...
...
Your node has successfully been instructed to join the cluster as a worker!
...

Using the kubeconfig as described in this section, you should now be able to see the new node in the cluster:

$ kubectl get no
NAME        STATUS   ROLES    AGE   VERSION
machine-0   Ready    <none>   10m   v1.32.0
machine-1   Ready    <none>   37s   v1.32.0

Medium-Touch Scenario

Use the following command to prepare the gardenadm medium-touch scenario:

make gardenadm-medium-touch-up

This will first build the needed images and then render the needed manifests for gardenadm bootstrap to the ./example/gardenadm-local/medium-touch directory.

Afterward, you can use go run to execute gardenadm commands on your machine:

$ go run ./cmd/gardenadm -h
gardenadm bootstraps and manages autonomous shoot clusters in the Gardener project.
...

Running E2E Tests for gardenadm

Based on the described setup, you can execute the e2e test suite for gardenadm:

make gardenadm-high-touch-up gardenadm-medium-touch-up
make test-e2e-local-gardenadm

You can also selectively run the e2e tests for one of the scenarios:

make gardenadm-high-touch-up
./hack/test-e2e-local.sh gardenadm --label-filter="high-touch" ./test/e2e/gardenadm/...

Tear Down the KinD Cluster

make kind-down