k8s-新增master节点

在当前唯一的master节点上运行如下命令
第一步：
kubeadm init phase upload-certs --upload-certs
执行结果如下：
1 # kubeadm init phase upload-certs --upload-certs
2 I1109 14:34:00.836965    5988 version.go:255] remote version is much newer: v1.25.3; falling back to: stable-1.22
3 [upload-certs] Storing the certificates in Secret "kubeadm-certs" in the "kube-system" Namespace
4 [upload-certs] Using certificate key:
5 ecf2abbfdf3a7bc45ddb2de75152ec12889971098d69939b98e4451b53aa3033

第二步：

kubeadm token create --print-join-command
执行结果如下
[root@k8s-master ~]# kubeadm token create --print-join-command
kubeadm join 172.16.0.1:6443 --token xxxxxx --discovery-token-ca-cert-hash sha256:xxxxxxx
第三步：
将得到的token和key进行拼接，得到如下命令：
kubeadm join 172.16.0.1:6443 --token xxxxxxxxx --discovery-token-ca-cert-hash xxxxxxx --control-plane --certificate-key xxxxxxx
注意事项：
  1. 不要使用 --experimental-control-plane，会报错
  2. 要加上--control-plane --certificate-key ，不然就会添加为node节点而不是master
  3. join的时候节点上不要部署，如果部署了kubeadm reset后再join
 
第四步：
join之后在原先唯一的master节点上成功后，显示如下消息：
This node has joined the cluster and a new control plane instance was created:

* Certificate signing request was sent to apiserver and approval was received.
* The Kubelet was informed of the new secure connection details.
* Control plane (master) label and taint were applied to the new node.
* The Kubernetes control plane instances scaled up.
* A new etcd member was added to the local/stacked etcd cluster.

To start administering your cluster from this node, you need to run the following as a regular user:

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

Run 'kubectl get nodes' to see this node join the cluster.

这样，我们在任何一个master节点上使用命令

kubectl get nodes
都能看到现在是全部的节点：
# kubectl get nodes
NAME          STATUS   ROLES    AGE   VERSION
k8s-master    Ready    master   57m   v1.25.3
k8s-master1   Ready    master   21m   v1.25.3
k8s-master2   Ready    master   21m   v1.25.3
k8s-node1     Ready    <none>   56m   v1.25.3
k8s-node2     Ready    <none>   56m   v1.25.3
k8s-node3     Ready    <none>   56m   v1.25.3
k8s-node4     Ready    <none>   56m   v1.25.3
k8s-node5     Ready    <none>   56m   v1.25.3
报错：
1. 第一次加入集群的时候会有以下报错：
 1 [preflight] Running pre-flight checks
 2 [preflight] Reading configuration from the cluster...
 3 [preflight] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -oyaml'
 4 error execution phase preflight:
 5 One or more conditions for hosting a new control plane instance is not satisfied.
 6 
 7 unable to add a new control plane instance a cluster that doesn't have a stable controlPlaneEndpoint address
 8 
 9 Please ensure that:
10 * The cluster has a stable controlPlaneEndpoint address.
11 * The certificates that must be shared among control plane instances are provided.
12 
13 
14 To see the stack trace of this error execute with --v=5 or higher
解决办法如下：
查看kubeadm-config.yaml
kubectl -n kube-system get cm kubeadm-config -oyaml
发现没有controlPlaneEndpoint
添加controlPlaneEndpoint
kubectl -n kube-system edit cm kubeadm-config
大概在这么个位置：
kind: ClusterConfiguration
kubernetesVersion: v1.25.3
controlPlaneEndpoint: 172.16.0.1:6443
然后再在准备添加为master的节点上执行kubeadm join的命令

 

补充：

如果etcd是外部集群，需要 加入配置文件生成 --certificate-key，排错知识来源：链接文档
kubeadm init phase upload-certs --upload-certs --config kubeadm-config.yaml
再重新加入

 

posted @ 2023-01-11 18:25  浅雨凉  阅读(3963)  评论(0)  编辑  收藏  举报