coredns.yaml

# Copyright (c) 2022 Gitpod GmbH. All rights reserved.
# Licensed under the GNU Affero General Public License (AGPL).
# See License.AGPL.txt in the project root for license information.

apiVersion: v1
kind: ServiceAccount
metadata:
  name: coredns
  namespace: kube-system
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRole
metadata:
  labels:
    kubernetes.io/bootstrapping: rbac-defaults
  name: system:coredns
rules:
- apiGroups:
  - ""
  resources:
  - endpoints
  - services
  - pods
  - namespaces
  verbs:
  - list
  - watch
- apiGroups:
  - discovery.k8s.io
  resources:
  - endpointslices
  verbs:
  - list
  - watch
---
apiVersion: rbac.authorization.k8s.io/v1beta1
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: v1
kind: ConfigMap
metadata:
  name: coredns
  namespace: kube-system
data:
  gitpod.db: |
    ; preview.gitpod-self-hosted.com test file
    preview.gitpod-self-hosted.com.       IN      SOA    sns.dns.icann.org. noc.dns.icann.org. 2015082541 7200 3600 1209600 3600
    preview.gitpod-self-hosted.com.       IN      CNAME  proxy.default.svc.cluster.local.
    *.preview.gitpod-self-hosted.com.     IN      CNAME  proxy.default.svc.cluster.local.
    *.ws.preview.gitpod-self-hosted.com.  IN      CNAME  proxy.default.svc.cluster.local.
  Corefile: |
    .:53 {
        errors
        health
        ready
        # extra configuration for `preview.gitpod-self-hosted.com`
        file /etc/coredns/gitpod.db preview.gitpod-self-hosted.com
        kubernetes cluster.local in-addr.arpa ip6.arpa {
          pods insecure
          fallthrough in-addr.arpa ip6.arpa
        }
        hosts /etc/coredns/NodeHosts {
          ttl 60
          reload 15s
          fallthrough
        }
        prometheus :9153
        forward . /etc/resolv.conf
        cache 30
        loop
        reload
        loadbalance
    }
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: coredns
  namespace: kube-system
  labels:
    k8s-app: kube-dns
    kubernetes.io/name: "CoreDNS"
spec:
  #replicas: 1
  strategy:
    type: RollingUpdate
    rollingUpdate:
      maxUnavailable: 1
  selector:
    matchLabels:
      k8s-app: kube-dns
  template:
    metadata:
      labels:
        k8s-app: kube-dns
    spec:
      priorityClassName: "system-cluster-critical"
      serviceAccountName: coredns
      tolerations:
        - key: "CriticalAddonsOnly"
          operator: "Exists"
        - key: "node-role.kubernetes.io/control-plane"
          operator: "Exists"
          effect: "NoSchedule"
        - key: "node-role.kubernetes.io/master"
          operator: "Exists"
          effect: "NoSchedule"
      nodeSelector:
        beta.kubernetes.io/os: linux
      containers:
      - name: coredns
        image: rancher/mirrored-coredns-coredns:1.9.1
        imagePullPolicy: IfNotPresent
        resources:
          limits:
            memory: 170Mi
          requests:
            cpu: 100m
            memory: 70Mi
        args: [ "-conf", "/etc/coredns/Corefile" ]
        volumeMounts:
        - name: config-volume
          mountPath: /etc/coredns
          readOnly: true
        ports:
        - containerPort: 53
          name: dns
          protocol: UDP
        - containerPort: 53
          name: dns-tcp
          protocol: TCP
        - containerPort: 9153
          name: metrics
          protocol: TCP
        securityContext:
          allowPrivilegeEscalation: false
          capabilities:
            add:
            - NET_BIND_SERVICE
            drop:
            - all
          readOnlyRootFilesystem: true
        livenessProbe:
          httpGet:
            path: /health
            port: 8080
            scheme: HTTP
          initialDelaySeconds: 60
          periodSeconds: 10
          timeoutSeconds: 1
          successThreshold: 1
          failureThreshold: 3
        readinessProbe:
          httpGet:
            path: /ready
            port: 8181
            scheme: HTTP
          initialDelaySeconds: 0
          periodSeconds: 2
          timeoutSeconds: 1
          successThreshold: 1
          failureThreshold: 3
      dnsPolicy: Default
      volumes:
        - name: config-volume
          configMap:
            name: coredns
            items:
            - key: gitpod.db
              path: gitpod.db
            - key: Corefile
              path: Corefile
            - key: NodeHosts
              path: NodeHosts
---
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
  clusterIP: 10.43.0.10
  ports:
  - name: dns
    port: 53
    protocol: UDP
  - name: dns-tcp
    port: 53
    protocol: TCP
  - name: metrics
    port: 9153
    protocol: TCP