执行下面命令初始化k8s集群时
代码语言：javascript复制kubeadm init --pod-network-cidr 10.21.0.0/16
--image-repository registry.cn-hangzhou.aliyuncs.com/google_containers通过 kubectl get pods -n kube-system 查看pods状态
发现coredns对应的pod状态为ContainerCreating，
通过kubectl describe pods -n kube-system coredns-6c76c8bb89-9br5d 查看对应pod状态有下面错误信息：
代码语言：javascript复制reate pod sandbox: rpc error: code = Unknown desc = [failed to set up sandbox container "5ac64afb8a4f7c98aeeb5f459a80410cb9b180ad92322adc0bfe0b9ce1c81107" network for pod "coredns-6c76c8bb89-jlzgn": networkPlugin cni failed to set up pod "coredns-6c76c8bb89-jlzgn_kube-system" network: error getting ClusterInformation: Get https://[10.96.0.1]:443/apis/crd.projectcalico.org/v1/clusterinformations/default: x509: certificate signed by unknown authority (possibly because of "crypto/rsa: verification error" while trying to verify candidate authority certificate "kubernetes"), failed to clean up sandbox container "5ac64afb8a4f7c98aeeb5f459a80410cb9b180ad92322adc0bfe0b9ce1c81107" network for pod "coredns-6c76c8bb89-jlzgn": networkPlugin cni failed to teardown pod "coredns-6c76c8bb89-jlzgn_kube-system" network: error getting ClusterInformation: Get https://[10.96.0.1]:443/apis/crd.projectcalico.org/v1/clusterinformations/default: x509: certificate signed by unknown authority (possibly because of "crypto/rsa: verification error" while trying to verify candidate authority certificate "kubernetes")]网上搜索一圈无效后又研究了下kubeadm reset命令执行后的输出结果：
代码语言：javascript复制The reset process does not clean CNI configuration. To do so, you must remove /etc/cni/net.d
The reset process does not reset or clean up iptables rules or IPVS tables.
If you wish to reset iptables, you must do so manually by using the "iptables" command.
If your cluster was setup to utilize IPVS, run ipvsadm --clear (or similar)
to reset your system's IPVS tables.
The reset process does not clean your kubeconfig files and you must remove them manually.
Please, check the contents of the $HOME/.kube/config file.然后根据上面的提示把/etc/cni/net.d目录删掉，然后重新执行kubeadm init命令就可以了。
