在kubernetes集群中获取节点时出错.连接被拒绝错误

Question

在从master获取kubernetes集群的节点时，我收到了拒绝连接错误。我试过互联网上所有可用的调试方法，但似乎都不起作用。我在集群中设置了一个主节点和两个工作节点。

1. kubectl获取节点

   master@master-vm:~$ kubectl get nodes
   The connection to the server X.X.X.X:6443 was refused - did you specify the right host or port?
   master@master-vm:~$
   

2. Kubelet状态

   master@master-vm:~/.kube$ systemctl status kubelet
   Active: active (running) since Tue 2021-03-16 19:53:33 IST; 20s ago
   kubelet.go:2263] node "master-vm" not found
   

3. Docker状态

   master@master-vm:~$ systemctl status docker
   ● docker.service - Docker Application Container Engine
   Loaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: enabled)
   Active: active (running) since Tue 2021-03-16 19:37:59 IST;
   

4. 6443 netstat中的端口详细信息

   master@master-vm:~$ sudo netstat -pnlt | grep 6443
   [sudo] password for master:
   tcp6      76      0 :::6443                 :::*                    LISTEN      1107/kube-apiserver
   master@master-vm:~$
   

5. 交换关闭

   master@master-vm:~$ sudo swapoff -a
   master@master-vm:~$ free -m
   total        used        free      shared  buff/cache   available
   Mem:           3936        1159        1468          11        1307        2545
   Swap:             0           0           0
   master@master-vm:~$
   

6. Kuectl版本

   master@master-vm:~$ kubectl version
   Client Version: version.Info{Major:"1", Minor:"17", 
   GitVersion:"v1.17.4",
   GitCommit:"8d8aa39598534325ad77120c120a22b3a990b5ea", 
   GitTreeState:"clean", 
   BuildDate:"2020-03-12T21:03:42Z", 
   GoVersion:"go1.13.8", 
   Compiler:"gc", 
   Platform:"linux/amd64"}
   The connection to the server X.X.X.X:6443 was refused - did you specify the right host or port?
   master@master-vm:~$
   

7. 防火墙状态

   master@master-vm:~$ sudo ufw status verbose #ubuntu
   Status: inactive
   master@master-vm:~$ sudo ufw disable #ubuntu
   Firewall stopped and disabled on system startup
   master@master-vm:~$
   

8. /etc/hosts

   127.0.0.1       localhost
   127.0.1.1       master-vm
   

9. Kubeadm版本

   master@master-vm:~$ kubeadm version
   kubeadm version: &version.Info{Major:"1", Minor:"17", 
   GitVersion:"v1.17.4", 
   GitCommit:"8d8aa39598534325ad77120c120a22b3a990b5ea", 
   GitTreeState:"clean", 
   BuildDate:"2020-03-12T21:01:11Z", 
   GoVersion:"go1.13.8", 
   Compiler:"gc", 
   Platform:"linux/amd64"}
   master@master-vm:~$ 
   

10. Kuectl配置视图

    master@master-vm:~/.kube$ kubectl config view
    apiVersion: v1
    clusters:
    cluster:
    certificate-authority-data: DATA+OMITTED
    server: https://X.X.X.X:6443
    name: kubernetes
    contexts:
    context:
    cluster: kubernetes
    user: kubernetes-admin
    name: kubernetes-admin@kubernetes
    current-context: kubernetes-admin@kubernetes
    kind: Config
    preferences: {}
    users:
    name: kubernetes-admin
    user:
    client-certificate-data: REDACTED
    client-key-data: REDACTED
    master@master-vm:~/
    

关于如何纠正上述错误，有什么建议吗？

Answer 1

在我看来，api服务器运行在ipv6上(注意netstat输出中的tcp6(。

尝试使用启动您的K8

kubeadm init --apiserver-advertise-address=<private-ipv4 of master host>

--apiserver-advertise-address-API服务器将公布其正在侦听的IP地址。如果未设置，将使用默认网络接口。

如果这没有帮助，您可能需要查看api服务器日志。使用docker logs获取日志或：

cat /var/log/pods/kube-system_kube-apiserver-master-vm_xxxxxxx/kube-apiserver/0.log

Answer 2

尝试在主节点上执行以下代码行。

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

接下来尝试在同一个主节点上执行kubectl get nodes，它应该可以正常工作。