k8s 域名解析 coredns

coredns自定义域名解析。

因为一些内网的自定义域名需要解析，这里通过coredns配置来处理

kubectl edit configmap -n kube-system coredns

apiVersion: v1
data:
  Corefile: |
    .:53 {
        errors
        health {
           lameduck 5s
        }
        ready
        kubernetes cluster.local in-addr.arpa ip6.arpa {
           pods insecure
           fallthrough in-addr.arpa ip6.arpa
           ttl 30
        }
        prometheus :9153
        forward . /etc/resolv.conf {
           max_concurrent 1000
        }
        cache 30
        loop
        reload
        loadbalance
        hosts { // 此处新增 
            192.168.0.51 gitea.zkldragon.org
            fallthrough
        }

    }
kind: ConfigMap
metadata:
  creationTimestamp: "2023-03-16T08:55:23Z"
  managedFields:
  - apiVersion: v1
    fieldsType: FieldsV1
    fieldsV1:
      f:data: {}
    manager: kubeadm
    operation: Update
    time: "2023-03-16T08:55:23Z"
  - apiVersion: v1
    fieldsType: FieldsV1
    fieldsV1:
      f:data:
        f:Corefile: {}
    manager: kubectl
    operation: Update
    time: "2023-03-22T10:50:53Z"
  name: coredns
  namespace: kube-system
  resourceVersion: "1325386"
  selfLink: /api/v1/namespaces/kube-system/configmaps/coredns
  uid: b6270bb0-e716-4da5-bb58-3c31bcc7ca68

--- 可以看下

coredns.ymal  -- 配置

---
kind: ReplicaSet
metadata:
  annotations:
    deployment.kubernetes.io/desired-replicas: '2'
    deployment.kubernetes.io/max-replicas: '3'
  labels:
    k8s-app: kube-dns
    pod-template-hash: 66db54ff7f
  name: coredns-66db54ff7f
  namespace: kube-system
  ownerReferences:
    - apiVersion: apps/v1
      blockOwnerDeletion: true
      controller: true
      kind: Deployment
      name: coredns
      uid: 0fa71939-8581-4723-9b1a-9e00f202b673
  resourceVersion: '628'
spec:
  replicas: 2
  selector:
    matchLabels:
      k8s-app: kube-dns
      pod-template-hash: 66db54ff7f
  template:
    metadata:
      creationTimestamp: null
      labels:
        k8s-app: kube-dns
        pod-template-hash: 66db54ff7f
    spec:
      containers:
        - args:
            - '-conf'
            - /etc/coredns/Corefile
          image: 'registry.aliyuncs.com/k8sxio/coredns: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
        - effect: NoSchedule
          key: node-role.kubernetes.io/master
      volumes:
        - configMap:
            defaultMode: 420
            items:
              - key: Corefile
                path: Corefile
            name: coredns
          name: config-volume
status:
  availableReplicas: 2
  fullyLabeledReplicas: 2
  observedGeneration: 1
  readyReplicas: 2
  replicas: 2