k3d

k3s in docker

k3s is the lightweight Kubernetes distribution by Rancher: rancher/k3s

This repository is based on @zeerorg's zeerorg/k3s-in-docker, reimplemented in Go by @iwilltry42 in iwilltry42/k3d, which is now rancher/k3d.

Requirements

• docker

Get

You have several options there:

• use the install script to grab the latest release:
  • wget: wget -q -O - https://raw.githubusercontent.com/rancher/k3d/master/install.sh | bash
  • curl: curl -s https://raw.githubusercontent.com/rancher/k3d/master/install.sh | bash
• Grab a release from the release tab and install it yourself.
• Via go: go install github.com/rancher/k3d (Note: this will give you unreleased/bleeding-edge changes)

or...

Build

1. Clone this repo, e.g. via go get -u github.com/rancher/k3d
2. Inside the repo run
   • 'make install-tools' to make sure required go packages are installed
3. Inside the repo run
   • make build to build for your current system
   • go install to install it to your GOPATH (Note: this will give you unreleased/bleeding-edge changes)
   • make build-cross to build for all systems

Usage

Check out what you can do via k3d help

Example Workflow: Create a new cluster and use it with kubectl

1. k3d create to create a new single-node cluster (docker container)
2. export KUBECONFIG=$(k3d get-kubeconfig) to make kubectl to use the kubeconfig for that cluster
3. execute some commands like kubectl get pods --all-namespaces
4. k3d delete to delete the default cluster

Expose services

1. via Ingress

1. Create a cluster, mapping the ingress port 80 to localhost:8081

   k3d create --api-port 6550 --publish 8081:80 --workers 2

2. Get the kubeconfig file

   export KUBECONFIG="$(k3d get-kubeconfig --name='k3s-default')"

3. Create a nginx deployment

   kubectl create deployment nginx --image=nginx

4. Create a ClusterIP service for it

   kubectl create service clusterip nginx --tcp=80:80

5. Create an ingress object for it with kubectl apply -f

   apiVersion: extensions/v1beta1
   kind: Ingress
   metadata:
     name: nginx
     annotations:
       ingress.kubernetes.io/ssl-redirect: "false"
   spec:
     rules:
     - http:
         paths:
         - path: /
           backend:
             serviceName: nginx
             servicePort: 80
   

6. Curl it via localhost

   curl localhost:8081/

2. via NodePort

1. Create a cluster, mapping the port 30080 from worker-0 to localhost:8082

   k3d create --publish 8082:30080@k3d-k3s-default-worker-0 --workers 2 -a 6550

... (Steps 2 and 3 like above) ...

4. Create a NodePort service for it with kubectl apply -f

   apiVersion: v1
   kind: Service
   metadata:
     labels:
       app: nginx
     name: nginx
   spec:
     ports:
     - name: 80-80
       nodePort: 30080
       port: 80
       protocol: TCP
       targetPort: 80
     selector:
       app: nginx
     type: NodePort
   

5. Curl it via localhost

   curl localhost:8082/