Kubernetes: Creating a Static Pod

kind static pod Kubernetes Pod

3 min read | by Jordi Prats

Static pods are managed directly by the kubelet without relying on the Kubernetes API server. Unlike regular pods, static pods are defined as manifest files placed in a specific directory on the node.

Since static pods are bound to a specific node, they are suffixed with the node hostname in the pod name. In this post, we will create a static pod in a kind cluster by mounting a directory from the host to the kubelet's static pod directory.

First we'll have to create a file with the static pod definition, then we'll create a kind cluster with a configuration that mounts the directory containing the static pod manifest.

apiVersion: v1 kind: Pod metadata:  name: demo-static-pod  namespace: kube-system spec:  containers:  - name: web  image: nginx  ports:  - name: web  containerPort: 80  protocol: TCP

We need to add this file to the /etc/kubernetes/manifests directory on the node that we want it to run. To do this in a kind cluster, we can mount a directory from the host to the control plane node:

kind: Cluster apiVersion: kind.x-k8s.io/v1alpha4 nodes:  - role: control-plane  extraMounts:  - hostPath: /Users/jordiprats/tmp/kind-static  containerPath: /etc/kubernetes/manifests

We can not create the cluster using:

kind create cluster -n static --config static-kind.yaml

Once created, we can check if the pod is running in the kube-system namespace:

$ kubectl get pods -n kube-system NAME READY STATUS RESTARTS AGE coredns-668d6bf9bc-6d4g6 1/1 Running 0 24s coredns-668d6bf9bc-776l6 1/1 Running 0 24s demo-static-pod-static-control-plane 1/1 Running 0 34s etcd-static-control-plane 1/1 Running 0 31s kindnet-rlljv 1/1 Running 0 24s kube-apiserver-static-control-plane 1/1 Running 0 31s kube-controller-manager-static-control-plane 1/1 Running 0 31s kube-proxy-h2ktn 1/1 Running 0 24s kube-scheduler-static-control-plane 1/1 Running 0 31s

As you can see, the Pod name is suffixed with the node hostname, in this case static-control-plane. In addition, the Pod definition will contain additional annotations and a owner reference to the node:

apiVersion: v1 kind: Pod metadata:  annotations:  kubernetes.io/config.hash: e316cce1f609de50dda0b065f293a8e1  kubernetes.io/config.mirror: e316cce1f609de50dda0b065f293a8e1  kubernetes.io/config.seen: "2025-02-15T16:17:52.340240888Z"  kubernetes.io/config.source: file  creationTimestamp: "2025-02-15T16:18:40Z"  name: demo-static-pod-static-control-plane  namespace: kube-system  ownerReferences:  - apiVersion: v1  controller: true  kind: Node  name: static-control-plane  uid: 4c700dd7-c4e7-4042-8be8-ac4f70ff7313  resourceVersion: "548"  uid: 9818e55d-84ca-478a-9d23-a27d804ec7ea spec: (...)

Posted on 24/02/2025

Categories