istio-federation-demo

gistfile1.txt

# Charmed k8s enforces its own coredns config which you cannot override and it gets reverted. 
# So had to set the dns option to "none" on the k8s master charm. 
# (You can apparently extend the coreDNS config by using coredns-custom but I didn't try it)
# then had to manually deploy the coredns using this: 


---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: coredns
  namespace: kube-system
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  labels:
    kubernetes.io/bootstrapping: rbac-defaults
  name: system:coredns
rules:
- apiGroups:
  - ""
  resources:
  - endpoints
  - services
  - pods
  - namespaces
  verbs:
  - list
  - watch
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  annotations:
    rbac.authorization.kubernetes.io/autoupdate: "true"
  labels:
    kubernetes.io/bootstrapping: rbac-defaults
  name: system:coredns
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: system:coredns
subjects:
- kind: ServiceAccount
  name: coredns
  namespace: kube-system
---
apiVersion: apps/v1
kind: Deployment
metadata:
  annotations:
    deployment.kubernetes.io/revision: "1"
  labels:
    cdk-restart-on-ca-change: "true"
    k8s-app: kube-dns
    kubernetes.io/name: CoreDNS
  managedFields:
  - apiVersion: apps/v1
    fieldsType: FieldsV1
    fieldsV1:
      f:metadata:
        f:annotations:
          .: {}
          f:kubectl.kubernetes.io/last-applied-configuration: {}
        f:labels:
          .: {}
          f:cdk-addons: {}
          f:cdk-restart-on-ca-change: {}
          f:k8s-app: {}
          f:kubernetes.io/name: {}
      f:spec:
        f:progressDeadlineSeconds: {}
        f:replicas: {}
        f:revisionHistoryLimit: {}
        f:selector:
          f:matchLabels:
            .: {}
            f:k8s-app: {}
        f:strategy:
          f:rollingUpdate:
            .: {}
            f:maxSurge: {}
            f:maxUnavailable: {}
          f:type: {}
        f:template:
          f:metadata:
            f:labels:
              .: {}
              f:k8s-app: {}
          f:spec:
            f:affinity:
              .: {}
              f:podAntiAffinity:
                .: {}
                f:requiredDuringSchedulingIgnoredDuringExecution: {}
            f:containers:
              k:{"name":"coredns"}:
                .: {}
                f:args: {}
                f:image: {}
                f:imagePullPolicy: {}
                f:livenessProbe:
                  .: {}
                  f:failureThreshold: {}
                  f:httpGet:
                    .: {}
                    f:path: {}
                    f:port: {}
                    f:scheme: {}
                  f:initialDelaySeconds: {}
                  f:periodSeconds: {}
                  f:successThreshold: {}
                  f:timeoutSeconds: {}
                f:name: {}
                f:ports:
                  .: {}
                  k:{"containerPort":53,"protocol":"TCP"}:
                    .: {}
                    f:containerPort: {}
                    f:name: {}
                    f:protocol: {}
                  k:{"containerPort":53,"protocol":"UDP"}:
                    .: {}
                    f:containerPort: {}
                    f:name: {}
                    f:protocol: {}
                  k:{"containerPort":9153,"protocol":"TCP"}:
                    .: {}
                    f:containerPort: {}
                    f:name: {}
                    f:protocol: {}
                f:readinessProbe:
                  .: {}
                  f:failureThreshold: {}
                  f:httpGet:
                    .: {}
                    f:path: {}
                    f:port: {}
                    f:scheme: {}
                  f:periodSeconds: {}
                  f:successThreshold: {}
                  f:timeoutSeconds: {}
                f:resources:
                  .: {}
                  f:limits:
                    .: {}
                    f:memory: {}
                  f:requests:
                    .: {}
                    f:cpu: {}
                    f:memory: {}
                f:securityContext:
                  .: {}
                  f:allowPrivilegeEscalation: {}
                  f:capabilities:
                    .: {}
                    f:add: {}
                    f:drop: {}
                  f:readOnlyRootFilesystem: {}
                f:terminationMessagePath: {}
                f:terminationMessagePolicy: {}
                f:volumeMounts:
                  .: {}
                  k:{"mountPath":"/etc/coredns"}:
                    .: {}
                    f:mountPath: {}
                    f:name: {}
                    f:readOnly: {}
            f:dnsPolicy: {}
            f:nodeSelector:
              .: {}
              f:kubernetes.io/os: {}
            f:priorityClassName: {}
            f:restartPolicy: {}
            f:schedulerName: {}
            f:securityContext: {}
            f:serviceAccount: {}
            f:serviceAccountName: {}
            f:terminationGracePeriodSeconds: {}
            f:tolerations: {}
            f:volumes:
              .: {}
              k:{"name":"config-volume"}:
                .: {}
                f:configMap:
                  .: {}
                  f:defaultMode: {}
                  f:items: {}
                  f:name: {}
                f:name: {}
    manager: kubectl
    operation: Update
    time: "2020-08-16T15:56:58Z"
  - apiVersion: apps/v1
    fieldsType: FieldsV1
    fieldsV1:
      f:metadata:
        f:annotations:
          f:deployment.kubernetes.io/revision: {}
      f:status:
        f:availableReplicas: {}
        f:conditions:
          .: {}
          k:{"type":"Available"}:
            .: {}
            f:lastTransitionTime: {}
            f:lastUpdateTime: {}
            f:message: {}
            f:reason: {}
            f:status: {}
            f:type: {}
          k:{"type":"Progressing"}:
            .: {}
            f:lastTransitionTime: {}
            f:lastUpdateTime: {}
            f:message: {}
            f:reason: {}
            f:status: {}
            f:type: {}
        f:observedGeneration: {}
        f:readyReplicas: {}
        f:replicas: {}
        f:updatedReplicas: {}
    manager: kube-controller-manager
    operation: Update
    time: "2020-08-16T15:57:24Z"
  name: coredns
  namespace: kube-system
  resourceVersion: "39611"
  selfLink: /apis/apps/v1/namespaces/kube-system/deployments/coredns
  uid: 7c43624b-69ba-4486-9787-f46e1c8b2f67
spec:
  progressDeadlineSeconds: 600
  replicas: 1
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      k8s-app: kube-dns
  strategy:
    rollingUpdate:
      maxSurge: 25%
      maxUnavailable: 1
    type: RollingUpdate
  template:
    metadata:
      creationTimestamp: null
      labels:
        k8s-app: kube-dns
    spec:
      affinity:
        podAntiAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
          - labelSelector:
              matchExpressions:
              - key: k8s-app
                operator: In
                values:
                - kube-dns
            topologyKey: kubernetes.io/hostname
      containers:
      - args:
        - -conf
        - /etc/coredns/Corefile
        image: rocks.canonical.com:443/cdk/coredns/coredns-amd64:1.6.7
        imagePullPolicy: IfNotPresent
        livenessProbe:
          failureThreshold: 5
          httpGet:
            path: /health
            port: 8080
            scheme: HTTP
          initialDelaySeconds: 60
          periodSeconds: 10
          successThreshold: 1
          timeoutSeconds: 5
        name: coredns
        ports:
        - containerPort: 53
          name: dns
          protocol: UDP
        - containerPort: 53
          name: dns-tcp
          protocol: TCP
        - containerPort: 9153
          name: metrics
          protocol: TCP
        readinessProbe:
          failureThreshold: 3
          httpGet:
            path: /ready
            port: 8181
            scheme: HTTP
          periodSeconds: 10
          successThreshold: 1
          timeoutSeconds: 1
        resources:
          limits:
            memory: 170Mi
          requests:
            cpu: 100m
            memory: 70Mi
        securityContext:
          allowPrivilegeEscalation: false
          capabilities:
            add:
            - NET_BIND_SERVICE
            drop:
            - all
          readOnlyRootFilesystem: true
        terminationMessagePath: /dev/termination-log
        terminationMessagePolicy: File
        volumeMounts:
        - mountPath: /etc/coredns
          name: config-volume
          readOnly: true
      dnsPolicy: Default
      nodeSelector:
        kubernetes.io/os: linux
      priorityClassName: system-cluster-critical
      restartPolicy: Always
      schedulerName: default-scheduler
      securityContext: {}
      serviceAccount: coredns
      serviceAccountName: coredns
      terminationGracePeriodSeconds: 30
      tolerations:
      - key: CriticalAddonsOnly
        operator: Exists
      volumes:
      - configMap:
          defaultMode: 420
          items:
          - key: Corefile
            path: Corefile
          name: coredns
        name: config-volume
---
apiVersion: v1
kind: Service
metadata:
  name: kube-dns
  namespace: kube-system
  annotations:
    prometheus.io/port: "9153"
    prometheus.io/scrape: "true"
  labels:
    k8s-app: kube-dns
    kubernetes.io/cluster-service: "true"
    kubernetes.io/name: "CoreDNS"
spec:
  selector:
    k8s-app: kube-dns
  ports:
  - name: dns
    port: 53
    protocol: UDP
  - name: dns-tcp
    port: 53
    protocol: TCP
  - name: metrics
    port: 9153
    protocol: TCP
    
 # once deployed, you can find the service IP by using kubectl get svc. 
 # the next step is to update the kubelet config on the worker nodes
 # Usually this is done by the charm, note the clusterDNS field. 
 # This is inherited by all pods: 
 
 # Generated by kubernetes-worker charm, do not edit
address: 0.0.0.0
apiVersion: kubelet.config.k8s.io/v1beta1
authentication:
  anonymous:
    enabled: false
  x509:
    clientCAFile: /root/cdk/ca.crt
clusterDNS:
- 10.152.183.64
clusterDomain: cluster.local
failSwapOn: false
kind: KubeletConfiguration
port: 10250
resolvConf: /run/systemd/resolve/resolv.conf
tlsCertFile: /root/cdk/server.crt
tlsPrivateKeyFile: /root/cdk/server.key

# Restart the kubernetes worker service and kubelet service on the worker. 
# Next is detailed debugging via: 
https://kubernetes.io/docs/tasks/administer-cluster/dns-debugging-resolution/

#core dns config
kubectl apply -f - <<EOF
apiVersion: v1
kind: ConfigMap
metadata:
  name: coredns
  namespace: kube-system
data:
  Corefile: |
    .:53 {
        errors
        health
        kubernetes cluster.local in-addr.arpa ip6.arpa {
           pods insecure
           upstream
           fallthrough in-addr.arpa ip6.arpa
        }
        prometheus :9153
        proxy . /etc/resolv.conf
        cache 30
        loop
        reload
        loadbalance
    }
    global:53 {
        errors
        cache 30
        proxy . $(kubectl get svc -n istio-system istiocoredns -o jsonpath={.spec.clusterIP})
    }
EOF

kubectl apply -f - <<EOF
apiVersion: v1
kind: ConfigMap
metadata:
name: coredns
namespace: kube-system
data:
Corefile: |
.:53 {
errors
health
kubernetes cluster.local in-addr.arpa ip6.arpa {
pods insecure
upstream
fallthrough in-addr.arpa ip6.arpa
}
prometheus :9153
proxy . /etc/resolv.conf
cache 30
loop
reload
loadbalance
}
global:53 {
errors
cache 30
proxy . $(kubectl get svc -n istio-system istiocoredns -o jsonpath={.spec.clusterIP})
}
EOF