问题现象

部署完master节点以后，执行kubectl get cs命令来检测组件的运行状态时，报如下错误：

[root@k8s-master yum.repos.d]# 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"}                                                                            
[root@k8s-master yum.repos.d]# wget http://127.0.0.1:10251/healthz
--2020-11-14 00:10:51--  http://127.0.0.1:10251/healthz
Connecting to 127.0.0.1:10251... failed: Connection refused.

解决分析

出现这种情况，是/etc/kubernetes/manifests/下的kube-controller-manager.yaml和kube-scheduler.yaml设置的默认端口是0导致的，解决方式是注释掉对应的port即可，操作如下：

[root@k8s-master manifests]# ls
etcd.yaml  kube-apiserver.yaml  kube-controller-manager.yaml  kube-scheduler.yaml
[root@k8s-master manifests]# pwd
/etc/kubernetes/manifests
[root@k8s-master manifests]#

kube-controller-manager.yaml文件修改：注释掉27行,- --port=0
kube-scheduler.yaml配置修改：注释掉19行,- --port=0
然后在master节点上重启kubelet，systemctl restart kubelet.service，然后重新查看就正常了

[root@k8s-master manifests]# vim kube-controller-manager.yaml
[root@k8s-master manifests]# vim kube-scheduler.yaml
[root@k8s-master manifests]# vim kube-controller-manager.yaml
[root@k8s-master manifests]# systemctl restart kubelet.service
[root@k8s-master manifests]# kubectl get cs
Warning: v1 ComponentStatus is deprecated in v1.19+
NAME                 STATUS    MESSAGE             ERROR
scheduler            Healthy   ok                 
controller-manager   Healthy   ok                 
etcd-0               Healthy   {"health":"true"}