Questions tagged [kubelet]

The Kubernetes kubelet is the primary “node agent” that runs on each node. Questions about the kubelet are most likely OFF TOPIC FOR STACK OVERFLOW; consider asking cluster administration questions on another site like Server Fault.

The kubelet is a core part of that the primary “node agent” that runs on each node. The kubelet works in terms of a PodSpec. A PodSpec is a YAML or JSON object that describes a pod. The kubelet takes a set of PodSpecs that are provided through various mechanisms (primarily through the apiserver) and ensures that the containers described in those PodSpecs are running and healthy. The kubelet doesn’t manage containers which were not created by Kubernetes.

Application developers rarely need to be directly concerned with the kubelet operation or administration. Most questions about the kubelet are not programming-related and are off-topic for Stack Overflow; other sites like Server Fault or DevOps Stack Exchange would be more appropriate places to ask. On-topic questions might include, for example, the Go k8s.io/kubernetes/pkg/kubelet package.

Reference: http://kubernetes.io/docs/admin/kubelet/

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Why does kubeadm not start even after disabling swap?

I am trying to install kubernetes with kubeadm in my laptop which has Ubuntu 16.04. I have disabled swap, since kubelet does not work with swap on. The command I used is : swapoff -a I also commented out the reference to swap in /etc/fstab. #…
Pravin Kumar
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What happens if a configMap(/secret) mounted as a volume in a running pod, is deleted on the master?

Let's say I have a pod with a configMap (or secret) volume. ConfigMap (or secret) object is present during the pod's creation, but I delete the configMap(or secret) object on the master, while the pod is running. What is the expected behavior? Is it…
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kubernetes strategic merge patch

Hi I am following this doc https://github.com/kubernetes/kubernetes/blob/master/docs/devel/api-conventions.md#strategic-merge-patch for strategic-merge-patch to partially update the JSON objects using PATCH REST API. The document says that it can…
priyank
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Prometheus kubelet metrics with pod labels

I am trying to figure out how to get pod labels into the metric tags from kubelet metrics using prometheus-stack. In our environment, we need to hash pod names (due to length limitations) so our app name, env, and unit name are saved in pod…
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What is the best practice to rotate Kubernetes certificates

Currently I am using a script to renew Kubernetes certificates before they expire. But this is a manual process. I have to monitor expiration dates carefully and run this script beforehand. What's the recommended way to update all control plane…
Baris Simsek
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Overlapping kubelet's container_memory_rss metrics from OOMKilled pod

I'm investigating an OOM kill of one of services in my kubernetes cluster. One of the first things I did was to look at a grafana plot of memory usage of the pod that was killed and to my surprise I saw a big spike in memory usage just around the…
Nav
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kubelet.service: Unit entered failed state in not ready state node error from kubernetes cluster

I am trying to deploy an springboot microservices in kubernetes cluster having 1 master and 2 worker node. When I am trying to get the node state using the command sudo kubectl get nodes, I am getting one of my worker node is not ready. It showing…
Mr.DevEng
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how to enable kubelet logging verbosity

I want to set higher logging verbosity in my k8s setup. While i managed to enable verbosity for API server and Kubectl by --v=4 argument; I am having difficulties finding way to pass in this flag to Kubelet. I am using kubeadm init method to launch…
ankit patel
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Reasons of Pod Status Failed

If Pod's status is Failed, Kubernetes will try to create new Pods until it reaches terminated-pod-gc-threshold in kube-controller-manager. This will leave many Failed Pods in a cluster and need to be cleaned up. Are there other reasons except…
flyer
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"x509: certificate signed by unknown authority" when running kubelet

I'm trying to install kubernetes with kubelet 1.4.5 on CoreOS beta (1192.2.0). I'm using a slightly modified version of the controller and worker install scripts from https://github.com/coreos/coreos-kubernetes/tree/master/multi-node/generic so in…
ufk
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installing kubernetes on coreos with kubeconfig (instead of deprecated --api-server)

I have two coreos machines with CoreOS beta (1185.2.0). I install kuberentes with rkt containers using a modified script, the original script is at https://github.com/coreos/coreos-kubernetes/tree/master/multi-node/generic. the modified version is…
ufk
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What does Kubelet use to determine the ephemeral-storage capacity of the node?

I have Kubernetes cluster running on a VM. A truncated overview of the mounts is: $ df -h Filesystem Size Used Avail Use% Mounted on /dev/sda1 20G 4.5G 15G 24% / /dev/mapper/vg001-lv--docker 140G 33G …
Sam
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Kubeadm Init failed at boot up control plane (kubelet isn't running or healthy)

I am using centos7 and using the below command to the bootstrap Kubernetes control plane in Master node : kubeadm init --pod-network-cidr=192.168.0.0/16 -v=5 and below is the error : I1124 11:11:51.842474 5446 waitcontrolplane.go:87]…
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kubelet error:failed to update node lease

I setup my kubernetes cluster by kubeadm. at the last step. I need join my nodes to the master. So i copy the join command to the node to exec it and whitout err. Then i back to master to exec "kubectl get nodes". there just a master node and…
Esc
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How to install kubelet, kubectl, kubeadm from source codes?

Because I have modified the source codes of k8s and want to debug the k8s, I would like to build and install kubelet, kubectl, kubeadm from source codes. Now I have built the kubelet, kubectl, kubeadm and get the bin files. When I want to run…
Jeffrey
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