Microk8s registry

Simple build/import script

sudo microk8s ctr images ls
curl http://localhost:32000/v2/_catalog

Dockerfile

FROM alpine
ADD https://github.com/coredns/coredns/releases/download/v1.8.1/coredns_1.8.1_linux_amd64.tgz coredns_1.8.1_linux_amd64.tgz
RUN tar xf coredns_1.8.1_linux_amd64.tgz
ADD https://raw.githubusercontent.com/jeremybusk/share/master/Corefile conf/Corefile
COPY . /
CMD ./coredns -conf Corefile

build

#!/usr/bin/env bash
set -e
# DO NOT USE ":latest" tag as registry cache will ignore that tag
name=rdns-coredns:jtest1
sudo docker build . -t $name
sudo docker save $name > $name.tar
sudo microk8s ctr image import $name.tar
sudo microk8s ctr images ls | grep $name
# sudo microk8s ctr images rm $name  # if clean-up ever needed

rdns-coredns.yml

apiVersion: v1
kind: Service
metadata:
  name: rdns-coredns
  labels:
    run: rdns-coredns
spec:
  type: NodePort
  ports:
  - port: 53
    targetPort: 53
    protocol: TCP
    name: dns-tcp
  - port: 53
    protocol: UDP
    name: dns-udp
  selector:
    run: rdns-coredns
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: rdns-coredns
spec:
  selector:
    matchLabels:
      run: rdns-coredns
  replicas: 1
  template:
    metadata:
      labels:
        run: rdns-coredns
    spec:
      volumes:
      - name: secret-volume
        secret:
          secretName: rdns-coredns-secret
      - name: configmap-volume
        configMap:
          name: rdns-coredns-configmap
      containers:
      - name: rdns-coredns
        # image: rdns-coredns:latest
        # image: localhost:32000/rdns-coredns:latest
        # image: docker.io/library/rdns-coredns:jtest1
        image: rdns-coredns:jtest1
        ports:
        - containerPort: 53
          protocol: UDP
        - containerPort: 53
          protocol: TCP

Let's run a query

kubectl get pods -o=wide | grep coredns
host google.com <ip address from above>
or
kubectl get svc | grep coredns
nslookup -port=<port from above> google.com 127.0.0.1

https://microk8s.io/docs/registry-images

https://microk8s.io/docs/registry-built-in

https://microk8s.io/docs/registry-private

sudo vim /var/snap/docker/current/config/daemon.json

"insecure-registries" : ["x.x.x.y:32000"],

sudo microk8s ctr images ls name~='localhost:32000'

sudo microk8s ctr images rm localhost:32000/coredns:latest

https://stackoverflow.com/questions/58871139/how-to-remove-docker-images-added-to-microk8s-image-cache

https://discuss.kubernetes.io/t/registry-images/11272