无法通过 Kubernetes 中的 skydns 服务解析 'kubernetes'

Question

core@core-1-94 ~ $ kubectl exec -it busybox -- nslookup kubernetes
Server:    10.100.0.10
Address 1: 10.100.0.10

nslookup: can't resolve 'kubernetes'
core@core-1-94 ~ $ kubectl get svc --namespace=kube-system
NAME       LABELS                                                                           SELECTOR           IP(S)            PORT(S)
kube-dns   k8s-app=kube-dns,kubernetes.io/cluster-service=true,kubernetes.io/name=KubeDNS   k8s-app=kube-dns   10.100.0.10      53/UDP
                                                                                                                                53/TCP
kube-ui    k8s-app=kube-ui,kubernetes.io/cluster-service=true,kubernetes.io/name=KubeUI     k8s-app=kube-ui    10.100.110.236   80/TCP
core@core-1-94 ~ $ kubectl exec -it busybox -- nslookup kubernetes 10.100.0.10:53
Server:    10.100.0.10
Address 1: 10.100.0.10

nslookup: can't resolve 'kubernetes'
core@core-1-94 ~ $ kubectl get endpoints --namespace=kube-system
NAME       ENDPOINTS
kube-dns   10.244.31.16:53,10.244.31.16:53
kube-ui    10.244.3.2:8080
core@core-1-94 ~ $ kubectl exec -it busybox -- nslookup kubernetes 10.244.31.16:53
Server:    10.244.31.16
Address 1: 10.244.31.16

Name:      kubernetes
Address 1: 10.100.0.1

我认为 kube-dns 的服务不可用。

skydns-svc.yaml :

apiVersion: v1
kind: Service
metadata:
  name: kube-dns
  namespace: kube-system
  labels:
    k8s-app: kube-dns
    kubernetes.io/cluster-service: "true"
    kubernetes.io/name: "KubeDNS"
spec:
  selector:
    k8s-app: kube-dns
  clusterIP: 10.100.0.10
  ports:
  - name: dns
    port: 53
    protocol: UDP
  - name: dns-tcp
    port: 53
    protocol: TCP

谁能帮忙？

Answer 1

要使 DNS 正常工作，kubelet 需要在启动时传递标志 --cluster_dns= 和 --cluster_domain=cluster.local。此标志未包含在 the set of flags passed to the kubelet, so the kubelet won't try to contact the DNS pod that you've created for name resolution services. To fix this, you can modify the script to add these two flags to the kubelet and then when you create a DNS service, you need to make sure that you set the same ip address that you passed to the --cluster_dns flag as the portalIP field of the service spec like this 中。 有关任何其他信息，您可以查看 it.