Unable to connect to the server: x509
qlz@k8smaster:~/.kube$ kubectl get node
Unable to connect to the server: x509: certificate signed by unknown authority (possibly because of "crypto/rsa: verification error" while trying to verify candidate authority certificate "kubernetes")
qlz@k8smaster:~/.kube$ cd ..
qlz@k8smaster:~$ sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
cp: overwrite '/home/qlz/.kube/config'? y
qlz@k8smaster:~$ sudo chown $(id -u):$(id -g) $HOME/.kube/config
qlz@k8smaster:~$ kubectl get node
NAME STATUS ROLES AGE VERSION
k8smaster Ready control-plane,master 5m57s v1.23.5
使用了sudo kubeadm reset重置master，尽管config文件还存在，其实每次初始化时生成的admin.conf都不一样，里面是包含了certificate-authority-data和client-certificate-data信息。这个就是导致这个报错的主要原因。所以当初始化后，会提示你
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
work节点NotReady
节点上
qlz@k8snode1:/etc/kubernetes$ sudo systemctl status kubelet
● kubelet.service - kubelet: The Kubernetes Node Agent
Loaded: loaded (/lib/systemd/system/kubelet.service; enabled; vendor preset: enabled)
Drop-In: /etc/systemd/system/kubelet.service.d
└─10-kubeadm.conf
Active: active (running) since Sun 2022-04-03 01:44:17 UTC; 1min 2s ago
Docs: https://kubernetes.io/docs/home/
Main PID: 905283 (kubelet)
Tasks: 15 (limit: 9443)
Memory: 33.5M
CGroup: /system.slice/kubelet.service
└─905283 /usr/bin/kubelet --bootstrap-kubeconfig=/etc/kubernetes/bootstrap-kubelet.conf --kubeconfig=/etc/kubernetes/kubelet.conf --config=/var/lib/kubelet/config.yaml --network-plugin=cni --pod-infra-container-image=k8s.gcr.io/pause:3.6
Apr 03 01:44:58 k8snode1 kubelet[905283]: I0403 01:44:58.887804 905283 cni.go:240] "Unable to update cni config" err="no networks found in /etc/cni/net.d"
Apr 03 01:44:59 k8snode1 kubelet[905283]: E0403 01:44:59.194216 905283 kubelet.go:2347] "Container runtime network not ready" networkReady="NetworkReady=false reason:NetworkPluginNotReady message:docker: network plugin is not ready: cni config uninitialized"
Apr 03 01:45:03 k8snode1 kubelet[905283]: I0403 01:45:03.888507 905283 cni.go:240] "Unable to update cni config" err="no networks found in /etc/cni/net.d"
Apr 03 01:45:04 k8snode1 kubelet[905283]: E0403 01:45:04.205664 905283 kubelet.go:2347] "Container runtime network not ready" networkReady="NetworkReady=false reason:NetworkPluginNotReady message:docker: network plugin is not ready: cni config uninitialized"
Apr 03 01:45:08 k8snode1 kubelet[905283]: I0403 01:45:08.889083 905283 cni.go:240] "Unable to update cni config" err="no networks found in /etc/cni/net.d"
Apr 03 01:45:09 k8snode1 kubelet[905283]: E0403 01:45:09.217129 905283 kubelet.go:2347] "Container runtime network not ready" networkReady="NetworkReady=false reason:NetworkPluginNotReady message:docker: network plugin is not ready: cni config uninitialized"
Apr 03 01:45:13 k8snode1 kubelet[905283]: I0403 01:45:13.891027 905283 cni.go:240] "Unable to update cni config" err="no networks found in /etc/cni/net.d"
Apr 03 01:45:14 k8snode1 kubelet[905283]: E0403 01:45:14.229815 905283 kubelet.go:2347] "Container runtime network not ready" networkReady="NetworkReady=false reason:NetworkPluginNotReady message:docker: network plugin is not ready: cni config uninitialized"
Apr 03 01:45:18 k8snode1 kubelet[905283]: I0403 01:45:18.893054 905283 cni.go:240] "Unable to update cni config" err="no networks found in /etc/cni/net.d"
Apr 03 01:45:19 k8snode1 kubelet[905283]: E0403 01:45:19.241789 905283 kubelet.go:2347] "Container runtime network not ready" networkReady="NetworkReady=false reason:NetworkPluginNotReady message:docker: network plugin is not ready: cni config uninitialized"
发现"Unable to update cni config" err="no networks found in /etc/cni/net.d"
从master 复制一份过去，全部重启，恢复
