Common reasons why k8s nodes are NotReady

Reason 1: The kubelet of the node node is not started

Investigation process:

View kubelet logs

# 查看node详情
kubectl get node -o yaml

# 查看你systemd守护进程管理的组件日志
## kubelet是systemd方式运行的
## 实时滚动显示某个Unit的最新日志
journalctl -u kubelet -f

# 只查看今天的kubelet日志
## |less可以解决日志显示不全的问题
journalctl -u kubelet --since today |less

Solution:

systemctl enable --now kubelet

View kube-proxy logs

# 查看Pod部署的组件日志
## k8s的其他组件都是pod运行的
kubectl logs kube-proxy-xxx -n kube-system
## 持续查看日志
kubectl logs -f kube-proxy-xxx -n kube-system

View os log

# 从OS中查看日志
tail /var/log/messages
# 持续查看OS日志
tail -f /var/log/messages

Reason 2: The cni plugin is not installed

Solution:

安装cni插件