K8S - Cluster Maintenance

Maintenance Nodes

# move pods to other nodes and cordon the node
kubectl drain node1
# mark node unschedulable
kubectl cordon node1
# mark node schedulable
kubectl uncordon node1

Cluster Upgrade Process

• Compatible versions
  • kube-apiserver: v1.x
  • controller-manager, kube-scheduler: v1.(x-1) ~ v1.x
  • kubelet, kube-proxy: v1.(x-2) ~ v1.x
  • kubectl: v1.(x+1) ~ v1.(x-1)
• Supported versions
  • v1.(x-2) ~ v1.x (current)
  • You should upgrade by 1 minor version each time
• Kubeadm upgrade process
  • https://kubernetes.io/zh/docs/tasks/administer-cluster/kubeadm/kubeadm-upgrade/

Backup

• Resource Configuration
• ETCD Cluster
  • https://kubernetes.io/zh/docs/tasks/administer-cluster/configure-upgrade-etcd/#%E5%A4%87%E4%BB%BD-etcd-%E9%9B%86%E7%BE%A4
• Persistent Volumes