Cheat Sheet

Install
Latest
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snap install microk8s --classic
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Specific version
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snap install microk8s --classic --channel=1.17/stable
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Set group
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sudo usermod -a -G microk8s $USER
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Logout from your workstation session and login again.
Useful commands
Get kubeconfig
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microk8s.config > $HOME/.kube/config
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Reset cluster
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microk8s reset --destroy-storage
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References
​https://microk8s.io/docs/commands​
Built-in Registry
Push
Pushing to this insecure registry may fail in some versions of Docker unless the daemon is explicitly configured to trust this registry. To address this we need to edit /etc/docker/daemon.json and add:
/etc/docker/daemon.json
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{
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  "insecure-registries" : ["localhost:32000"]
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}
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Then restart docker.
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sudo systemctl restart docker
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Enable registry, build and push image.
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microk8s enable registry #20Gi registry
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#microk8s enable registry:size=40Gi
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​
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# Build image
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docker build . -t localhost:32000/myimage:registry
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​
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# Or tag an existing image
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#docker tag 1fe3d8f47868 localhost:32000/myimage:registry
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​
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docker push localhost:32000/myimage:registry
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Deploy it.
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apiVersion: apps/v1
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kind: Deployment
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metadata:
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  name: myapp
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  namespace: myapp
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  labels:
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    app: myapp
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spec:
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  selector:
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    matchLabels:
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      app: myapp
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  template:
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    metadata:
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      labels:
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        app: myapp
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    spec:
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      containers:
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      - name: myapp
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        image: localhost:32000/myimage:registry
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        imagePullPolicy: Always
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        ports:
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        - containerPort: 8000
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Remove
Run on your workstation:
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registry=localhost:32000
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repositories=$(curl ${registry}/v2/_catalog)
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for repo in $(echo "${repositories}" | jq -r '.repositories[]'); do
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  echo $repo
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  tags=$(curl -sSL "http://${registry}/v2/${repo}/tags/list" | jq -r '.tags[]')
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  for tag in $tags; do
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    echo $tag
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    curl -v -sSL -X DELETE "http://${registry}/v2/${repo}/manifests/$(
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      curl -sSL -I \
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          -H "Accept: application/vnd.docker.distribution.manifest.v2+json" \
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          "http://${registry}/v2/${repo}/manifests/$tag" \
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      | awk '$1 == "Docker-Content-Digest:" { print $2 }' \
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      | tr -d #x27;\r' \
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    )"
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  done
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done
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Then run:
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registry_pod=$(kubectl --namespace="container-registry" get pods --template '{{range .items}}{{.metadata.name}}{{"\n"}}{{end}}')
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kubectl exec --namespace="container-registry" $registry_pod /bin/registry garbage-collect /etc/docker/registry/config.yml
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Local private registry
Allow insecure registry:
/etc/docker/daemon.json
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{
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  "insecure-registries" : ["172.17.0.1:5001"]
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}
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​
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Restart docker.
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sudo systemctl restart docker
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Stop microk8s, backup and edit config file.
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microk8s stop
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sudo cp /var/snap/microk8s/current/args/containerd-template.toml /var/snap/microk8s/current/args/containerd-template.toml-BKP
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nano /var/snap/microk8s/current/args/containerd-template.toml
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Add the following section.
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...
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  [plugins."io.containerd.grpc.v1.cri".registry]
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...
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    [plugins."io.containerd.grpc.v1.cri".registry.mirrors]
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...
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      [plugins."io.containerd.grpc.v1.cri".registry.mirrors."172.17.0.1:5001"]
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        endpoint = ["http://172.17.0.1:5001"]
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Start microk8s.
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microk8s start
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Start local registry.
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docker run -it --rm \
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  -e REGISTRY_HTTP_ADDR=0.0.0.0:5001 \
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  -p 5001:5001 \
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  --name local-registry \
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  registry:2
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Tag and push image.
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docker tag ubuntu:18.04 172.17.0.1:5001/my-ubuntu:0.0.1
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docker push 172.17.0.1:5001/my-ubuntu:0.0.1
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curl 172.17.0.1:5001/v2/_catalog
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Test it.
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microk8s kubectl run -it --rm tmp --image=172.17.0.1:5001/my-ubuntu:0.0.1
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References
​https://microk8s.io/docs/registry-private​
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