Table of Contents

环境说明
#

Kubernetes Version: v1.20.4 (kubekey 部署)
操作系统: CentOS 7.9.2009
Rancher Version: v2.4.15

准备 k8s 模拟环境
#

此次将使用 kubekey 进行一键部署，kubekey 底层 集群部署 基于 kubeadm，感兴趣的话，可以前往 Github 地址进行详细了解。

编译安装 kubekey
#

省略系统初始化步骤，执行编译时，使用到了 docker 容器，请事先进行安装。对应系统初始步骤，可参考文档

yum install -y git 

git clone https://github.com/kubesphere/kubekey.git \
&& cd kubekey 

./build.sh -p  # 执行编译， 如需进行交叉编译，需要在此脚本中添加对应环境变量。

cp -a output/kk /usr/local/bin/ 

kk version # 如打印了下面字段，则表示成功
version.BuildInfo{Version:"latest+unreleased", GitCommit:"f3f9e2e2d001a1b35883f5baea07912bb636db56", GitTreeState:"clean", GoVersion:"go1.14.7"}

启动集群
#

mkdir -p  ~/kubekey-workspace

kk create config --with-kubernetes v1.20.4 # 初始化配置文件

cat config-sample.yaml 
apiVersion: kubekey.kubesphere.io/v1alpha1
kind: Cluster
metadata:
  name: sample
spec:
  hosts:
  - {name: node1, address: 192.168.8.70, internalAddress: 192.168.8.70, user: root, password: 123456}
  - {name: node2, address: 192.168.8.71, internalAddress: 192.168.8.71, user: root, password: 123456}
  roleGroups:
    etcd:
    - node1
    master: 
    - node1
    worker:
    - node1
    - node2
  controlPlaneEndpoint:
    domain: lb.kubesphere.local
    address: ""
    port: 6443
  kubernetes:
    version: v1.20.4
    imageRepo: kubesphere
    clusterName: cluster.local
  network:
    plugin: calico
    kubePodsCIDR: 10.233.64.0/18
    kubeServiceCIDR: 10.233.0.0/18
  registry:
    registryMirrors: []
    insecureRegistries: []
  addons: []
  
  
yum install socat conntrack -y # 安装依赖
 
kk create cluster -f ./config-sample.yaml  # 启动集群
+-------+------+------+---------+----------+-------+-------+-----------+---------+------------+-------------+------------------+--------------+
| name  | sudo | curl | openssl | ebtables | socat | ipset | conntrack | docker  | nfs client | ceph client | glusterfs client | time         |
+-------+------+------+---------+----------+-------+-------+-----------+---------+------------+-------------+------------------+--------------+
| node2 | y    | y    | y       | y        | y     | y     | y         | 20.10.7 |            |             |                  | CST 09:39:04 |
| node1 | y    | y    | y       | y        | y     | y     | y         | 20.10.7 |            |             |                  | CST 09:39:04 |
+-------+------+------+---------+----------+-------+-------+-----------+---------+------------+-------------+------------------+--------------+

This is a simple check of your environment.
Before installation, you should ensure that your machines meet all requirements specified at
https://github.com/kubesphere/kubekey#requirements-and-recommendations

Continue this installation? [yes/no]: yes  # 输入 yes

Rancher 导入启动的集群
#

省略创建导入步骤。问题如下所示，dashbaord 界面 上提示 Scheduler & Controller 组件不健康

kubectl get cs
Warning: v1 ComponentStatus is deprecated in v1.19+
NAME                 STATUS      MESSAGE                                                                                       ERROR
scheduler            Unhealthy   Get "http://127.0.0.1:10251/healthz": dial tcp 127.0.0.1:10251: connect: connection refused   
controller-manager   Unhealthy   Get "http://127.0.0.1:10252/healthz": dial tcp 127.0.0.1:10252: connect: connection refused   
etcd-0               Healthy     {"health":"true"}

问题说明与修复
#

此问题原因为: 在较新版本 kubeadm 部署的集群中，默认将 http 通讯端口进行了关闭，导致在进行健康检查的使用无法进行通讯，自检失败。解决此方法的思路目前有两个，第一种 : 是将自检调用的端口更改为 https，第二种: 是将 http 端口监听进行修复开启。下面介绍使用第二种较为简单 的方法进行示例修复 (此方法有一定的安全风险，请自行评估使用)。

修复 http 端口的监听
#

由于使用的是 kubeadm 部署集群，更改对应静态 pod yaml 文件配置即可

vi /etc/kubernetes/manifests/kube-scheduler.yaml # 编辑 scheduler 配置文件
...
spec:
  containers:
  - command:
    - kube-scheduler
    - --authentication-kubeconfig=/etc/kubernetes/scheduler.conf
    - --authorization-kubeconfig=/etc/kubernetes/scheduler.conf
    - --bind-address=0.0.0.0
    - --feature-gates=CSINodeInfo=true,VolumeSnapshotDataSource=true,ExpandCSIVolumes=true,RotateKubeletClientCertificate=true,RotateKubeletServerCertificate=true
    - --kubeconfig=/etc/kubernetes/scheduler.conf
    - --leader-elect=true
#    - --port=0     # 将此段进行注解
...


vi /etc/kubernetes/manifests/kube-controller-manager.yaml # 同上一样 更改 controller 的配置文件
...
spec:
  containers:
  - command:
    - kube-controller-manager
    - --allocate-node-cidrs=true
    - --authentication-kubeconfig=/etc/kubernetes/controller-manager.conf
    - --authorization-kubeconfig=/etc/kubernetes/controller-manager.conf
    - --bind-address=0.0.0.0
    - --client-ca-file=/etc/kubernetes/pki/ca.crt
    - --cluster-cidr=10.233.64.0/18
    - --cluster-name=cluster.local
    - --cluster-signing-cert-file=/etc/kubernetes/pki/ca.crt
    - --cluster-signing-key-file=/etc/kubernetes/pki/ca.key
    - --controllers=*,bootstrapsigner,tokencleaner
    - --experimental-cluster-signing-duration=87600h
    - --feature-gates=CSINodeInfo=true,VolumeSnapshotDataSource=true,ExpandCSIVolumes=true,RotateKubeletServerCertificate=true
    - --kubeconfig=/etc/kubernetes/controller-manager.conf
    - --leader-elect=true
    - --node-cidr-mask-size=24
#    - --port=0
...

一键使用 sed 替换方式

sed -i 's/.*--port=0.*/#&/' /etc/kubernetes/manifests/kube-controller-manager.yaml
sed -i 's/.*--port=0.*/#&/' /etc/kubernetes/manifests/kube-scheduler.yaml

再次前往对应 dashboard 界面进行查看，可以看到已无之前的错误提示

kubectl get cs
Warning: v1 ComponentStatus is deprecated in v1.19+
NAME                 STATUS    MESSAGE             ERROR
controller-manager   Healthy   ok                  
scheduler            Healthy   ok                  
etcd-0               Healthy   {"health":"true"}