CoreDNS无法在Kubernetes集群中运行

我正在尝试设置Kubernetes集群,但我无法运行CoreDNS.我运行了以下命令来启动集群:

sudo swapoff -a
sudo sysctl net.bridge.bridge-nf-call-iptables=1
sudo kubeadm init

mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

kubectl apply -f "https://cloud.weave.works/k8s/net?k8s- version=$(kubectl version | base64 | tr -d '\n')"
kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/master/src/deploy/recommended/kubernetes-dashboard.yaml

为了检查POD kubectl get pods --all-namespaces,我明白了

NAMESPACE     NAME                                    READY   STATUS             RESTARTS   AGE
kube-system   coredns-68fb79bcf6-6s5bp                0/1     CrashLoopBackOff   6          10m
kube-system   coredns-68fb79bcf6-hckxq                0/1     CrashLoopBackOff   6          10m
kube-system   etcd-myserver                           1/1     Running            0          79m
kube-system   kube-apiserver-myserver                 1/1     Running            0          79m
kube-system   kube-controller-manager-myserver        1/1     Running            0          79m
kube-system   kube-proxy-9ls64                        1/1     Running            0          80m
kube-system   kube-scheduler-myserver                 1/1     Running            0          79m
kube-system   kubernetes-dashboard-77fd78f978-tqt8m   1/1     Running            0          80m
kube-system   weave-net-zmhwg                         2/2     Running            0          80m

所以CoreDNS不断崩溃.我能找到的唯一错误消息来自 /var/log/syslog:

Oct  4 18:06:44 myserver kubelet[16397]: E1004 18:06:44.961409   16397 pod_workers.go:186] Error syncing pod c456a48b-c7c3-11e8-bf23-02426706c77f ("coredns-68fb79bcf6-6s5bp_kube-system(c456a48b-c7c3-11e8-bf23-02426706c77f)"), skipping: failed to "StartContainer" for "coredns" with CrashLoopBackOff: "Back-off 5m0s restarting failed container=coredns pod=coredns-68fb79bcf6-6s5bp_kube-system(c456a48b-c7c3-11e8-bf23-02426706c77f)"

来自kubectl logs coredns-68fb79bcf6-6s5bp -n kube-system:

.:53
2018/10/04 11:04:55 [INFO] CoreDNS-1.2.2
2018/10/04 11:04:55 [INFO] linux/amd64, go1.11, eb51e8b
CoreDNS-1.2.2
linux/amd64, go1.11, eb51e8b
2018/10/04 11:04:55 [INFO] plugin/reload: Running configuration MD5 = f65c4821c8a9b7b5eb30fa4fbc167769
2018/10/04 11:04:55 [FATAL] plugin/loop: Seen "HINFO IN 3256902131464476443.1309143030470211725." more than twice, loop detected

我发现的一些解决方案是要发布的

kubectl -n kube-system get deployment coredns -o yaml | \
sed 's/allowPrivilegeEscalation: false/allowPrivilegeEscalation: true/g' | \
kubectl apply -f -

并修改/etc/resolv.conf为指向实际的DNS,而不是localhost,我也尝试过.

该问题在https://kubernetes.io/docs/setup/independent/troubleshooting-kubeadm/#pods-in-runco​​ntainererror-crashloopbackoff-or-error-state中进行了描述,我尝试了许多不同的Pod网络,但没有任何帮助.

我跑sudo kubeadm reset && rm -rf ~/.kube/ && sudo kubeadm init了好几次.

我正在运行Ubuntu 16.04,Kubernetes 1.12和Docker 17.03.有任何想法吗？

我也有同样的问题.

我会通过删除cmred cm内的插件'loop'来解决问题.但我不知道这个云案例是否还有其他问题.

1,kubectl编辑cm coredns -n kube-system

2,删除'循环',保存并退出

3,重启coredns pods:"kubctel delete pod coredns .... -n kube-system"

使用这种方式可以解决一些问题：

打开并编辑coredns的配置图。

kubectl edit cm coredns -n kube-system

“将代理。/etc/resolv.conf替换为上游DNS的IP地址，例如代理8.8.8.8。” 根据coredns日志输出中的链接（在页面末尾）

保存并退出。

kubectl get pods -n kube-system -oname | grep coredns | xargs kubectl delete -n kube-system

在链接中说明了问题的原因。您可以在此cmd的输出中找到此链接

kubectl日志coredns-7d9cd4f75b-cpwxp -n kube-system

此链接在CoreDNS-1.2.4的输出中。

我使用此cmd升级CoreDNS

kubectl补丁程序部署-n = kube-system coredns -p'{“ spec”：{“ template”：{“ spec”：{“ containers”：[{“ image”：“ k8s.gcr.io/coredns:1.2。 4“，” name“：” coredns“，” resources“：{” limits“：{” memory“：” 1Gi“}，” requests“：{” cpu“：” 100m“，” memory“：” 70Mi“ }}}]}}}}'