Questions tagged [kubeadm]
The kubeadm tag has no usage guidance.
144
questions
20
votes
10
answers
44k
views
failed to run Kubelet: validate service connection: CRI v1 runtime API is not implemented for endpoint
I have installed kubelet 1.26.0 on Ubuntu 22.04 using apt install kubelet command, but when I try journalctl -xeu kubelet I get the following result:
░░
░░ The unit kubelet.service has entered the '...
- 427
12
votes
4
answers
33k
views
How do I check the max pod capacity of a Kubernetes node
I am busy setting up new k8s cluster.
I am using rke with the --max-pods: 200
kubelet: # https://rancher.com/docs/rke/latest/en/config-options/services/services-extras/#extra-args
extra_args:
...
- 654
5
votes
2
answers
11k
views
Kubeadm 1.24 with containerd. Kubeadm init fail (centos 7)
I try to install a single node cluster on centos 7, with kubadm 1.24 and with containerd,
i followed the installation steps,
and i did:
containerd config default > /etc/containerd/config.toml
and ...
- 81
4
votes
3
answers
8k
views
kubernetes coredns is in CrashLoopBackOff status with "no nameservers found" error
I have tried to build kubernetes using kubeadm on my bare-metal server with containerd as cri, but it seemed that coredns failed to start after installing cni (weave-net).
Two coredns containers are ...
- 393
4
votes
2
answers
2k
views
All kube-system pods keep crashing, etcd receives sigterm
I'm trying to set up an on-premises Kubernetes cluster. For starters I used kubeadm to initialize my control plane on one node. But all kube-system pods constantly crash. I took a deep look into the ...
- 143
4
votes
1
answer
3k
views
Kubernetes: Pod IP address is out of range specified in --pod-network-cidr
After upgrading to v1.24.0 (after Dockershim removal), I had to install cri-dockerd,
then I did the following:
sudo kubeadm init --pod-network-cidr=10.244.0.0/16 --cri-socket=unix:///var/run/cri-...
- 101
4
votes
1
answer
6k
views
Which certificate does kubelet use?
This is a kubeadm based 1.16 cluster. The way I understand mTLS work between an apiserver & kubelet is:
apiserver -> kubelet
--kubelet-client-certificate & --kubelet-client-key => The ...
- 151
4
votes
2
answers
6k
views
What is the proper way to modify kubelet and control-plane configuration with kubeadm?
I've installed a kubernetes (v1.20.0) cluster with 3 masters and 3 nodes using kubeadm init and kubeadm join, all on Ubuntu 20.04. Now I need to update the configuration and
Add --cloud-provider=...
3
votes
2
answers
15k
views
Is it possible to change CIDR network flannel and Kubernetes
Is it possible to change CIDR network flannel on running Kubernetes cluster?
If yes what will happen with the launched pods?
Thanks
- 43
3
votes
3
answers
45k
views
Kubernetes API server not able to register master node
I was trying to create a Kubernetes Cluster using kubeadm. I had spin up an Ubuntu 18.04 server, installed docker (made it sure that docker.service was running), installed kubeadm kubelet and kubectl.
...
- 63
3
votes
1
answer
6k
views
How to change the hostname on the single-node K8s node
Environments:
OS: Ubuntu 18.04.5 LTS
Kubernetes: v1.16.15
deployment tool: kubeadm v1.16.15
I initialize a single-node K8s on my workstation with the following configuraions:
---
apiVersion: kubeadm....
- 31
3
votes
1
answer
9k
views
coredns pods stuck in Pending state
I'm trying to learn k8s and since I happen to have access to OpenStack cloud I figured I'll try to install k8s on it, following this wiki.
So far I was able to initialize cluster, install weave CNI, ...
3
votes
1
answer
967
views
Kubernetes cluster via kubeadm - CoreDNS buffer size too small / Pods network problems
I am new to deploying on-premise Kubernetes clusters. I managed to deploy one using kubeadm with weave CNI.
Internet connection inside Pods is somewhat sluggish / non-working. I am trying to deploy ...
- 31
2
votes
4
answers
25k
views
How can I find which kubernetes certificate has expired?
I have a kubeadm installed kubernetes cluster. Recently it stopped working. kubelet is running but seems stuck in initialization phases. I think the root cause is this recurring log in kube-apiserver:
...
- 301
2
votes
1
answer
4k
views
Update apiserver certificates for HA k8s cluster
I have HA k8s cluster that was created by kubeadm. I would like to update API server certificate to add additional SANs. For this purpose I followed some steps described in another post, but what I ...
- 123
2
votes
1
answer
21k
views
How to disable kubectl insecure approval towards the kube apiserver
I am trying to make my Master Server-API more secure in order to avoid allowing non https requests to go through.
Sample of config:
$ kubectl config view
apiVersion: v1
clusters:
- cluster:
server:...
- 533
2
votes
2
answers
13k
views
Error in configuration: context was not found for specified context: kind-kind
This is my skaffold.yaml file:
apiVersion: skaffold/v2alpha3
kind: Config
deploy:
kubeContext: kind-kind
kubectl:
manifests:
- ./infra/k8s/*
build:
local:
push: false
artifacts:
...
- 427
2
votes
1
answer
9k
views
It seems like the kubelet isn't running or healthy. [kubelet-check] The HTTP call equal to 'curl -sSL http://localhost:10248/healthz' failed with erro
I am trying to do sudo kubeadm init of kubeadm 1.26.0 on an Ubuntu 22.04 machine. But I get the following result:
[init] Using Kubernetes version: v1.26.0
[preflight] Running pre-flight checks
[...
- 427
2
votes
1
answer
3k
views
K8s: discovery Failed to request cluster-info (forbidden)
The command kubeadm join 192.168.178.38:6443 ... fails
The host/port is reachable. I tested it with telnet.
But I get this on the node:
[discovery] Failed to request cluster-info, will try again:
...
- 3,893
2
votes
1
answer
2k
views
Kubernets 1.21.3 The recommended value for "clusterCIDR" in "KubeProxyConfiguration"
I am trying to join new node to existing v1.21.3 cluster with Calico CNI. join command giving clusterCIDR warning.
How to fix this subnet warning message?
# kubeadm join master-vip:8443 --token xxx --...
- 243
2
votes
1
answer
2k
views
Warnings in kubeadm after migrating from docker to containerd
I run a kubernetes cluster, installed with kubeadm. I recently upgraded from 1.19 to 1.20 and migrated the container runtime from docker to containerd, since docker is now deprecated.
I configured ...
- 301
2
votes
1
answer
2k
views
AWS Cloud Provider Integration with Kubernetes - Nodes stuck with "uninitialized: true" taint after bootstrapping
Summary
I am attempting to bootstrap a Kubernetes cluster on AWS using Kubeadm. Please before you suggest them, I am not interested in using EKS or another bootstrapping solution like Kops, Kubespray,...
- 261
2
votes
1
answer
5k
views
Kubernetes Cluster on CentOS 7 with kubeadm 1.24 - calico => coredns stuck in ContainerCreating
In order to install a master kubernetes node on centos7 with containerd and calico :
I followed this steps : https://computingforgeeks.com/install-kubernetes-cluster-on-centos-with-kubeadm/
After the ...
- 81
2
votes
2
answers
797
views
How do I configure Kubernetes to use kubenet with kubeadm?
I deployed a Kubernetes cluster using kubeadm.
$ kubectl get nodes
NAME STATUS ROLES AGE VERSION
ip-172-31-33-9.us-east-2.compute....
- 129
2
votes
1
answer
2k
views
Kube-apiserver crashing
I am trying to create a kubernetes cluster on my local machine.
I created 3 vm's (two master and a slave).
I am using kubespray(v2.15.0) to create my cluster, But my kube-apiserver contianer keeps ...
- 23
2
votes
1
answer
193
views
Why does kubeproxy, apiserver and etcd not need CNI plugins to start?
I have initiated a k8s cluster on a server with the below configuration:
OS: Ubuntu 2022 LTS
Container Runtime: containerd
CNI: Absoloutley nothing installed!
Cluster initiator: Kubeadm
init-...
- 23
2
votes
0
answers
780
views
Changing out all Control Plane Nodes safely - Best Practice
I have a 3 control plane node HA kubeadm cluster that I need to completely replace. I have already replaced the worker nodes. How do I completely replace the control plane without downtime?
I use a LB ...
- 21
2
votes
0
answers
6k
views
Pod coredns stuck in ContainerCreating state with Weave on k8s
First of all, let me thank you for this amazing guide. I'm very new to kubernetes and having a guide like this to follow helps a lot when trying to setup my first cluster!
That said, I'm having some ...
- 123
1
vote
2
answers
6k
views
Kubeadm with containerd cannot use locally loaded images
I'm trying to build kubernetes with containerd in bare-metal server (RHEL8).
There's no Internet connection so I manually downloaded needed images (e.g. k8s.gcr.io/kube-scheduler:v1.22.1) and loaded ...
- 393
1
vote
1
answer
4k
views
Offline installation of kubernetes fails when using containerd as a CRI
I had to build a bare-metal Kubernetes cluster with no Internet connection for some reason.
As dockershim was deprecated, I decided to use containerd as a CRI, but the offline installation with ...
- 393
1
vote
1
answer
2k
views
kubeadm token create fails on self signed ca cert
I am trying to deploy a k8s cluster using kubespray on top of an openstack cluster of ubuntu servers. The install fails when kubeadm tries to init the cloud provider by submitting a post request to ...
- 111
1
vote
2
answers
1k
views
Deploy control plane without master node registration using kubeadm
I'd like to set up the Kubernetes cluster and hide the control plane components for all clients (some kind of a managed cluster). Kubeadm uses Kubelet and static pods to run this components which lead ...
- 123
1
vote
1
answer
3k
views
KubeADM cluster: how to configure DNS properly
I have the following project that I use to create my own Kubernetes cluster on the local machine (macOS) via KubeAdm: https://github.com/sasadangelo/k8s-cluster
Basically, I started from this project ...
1
vote
2
answers
3k
views
kubeadm - ERROR start version '' not supported
Recently I upgraded Kubernetes cluster from version 1.5.3 to 1.6.1 using kubeadm.
Now I would like to upgrade from version 1.6.1 to 1.6.2 but I'm facing this error:
[root@master ~]#kubeadm upgrade ...
- 121
1
vote
1
answer
77
views
In kubernetes DNS queries fail between nodes
I have an issue with kubernetes and coreDNS that I am not able to solve.
System information
1 master + 2 workers
Red Hat Enterprise Linux release 9.3 (Plow)
k8s: v1.28.7
flannel: v0.24.2
coreDNS: v1....
- 21
1
vote
1
answer
1k
views
kube-apiserver started to die on start-up after a few months of good work - how can I check its logs?
The stage: a control plane machine, kubernetes 1.24.3 on a baremetal Ubuntu 22.04, installed with kubeadm, there is also one worker node. The whole set-up worked like a charm for 4 months until some ...
- 123
1
vote
1
answer
452
views
VMWare Workstation and Windows 10: can't connect to a server hosted on VM
I have a private 2 nodes Kubernetes cluster configured on VMWare Workstation 15. I'm using MetalLB and Calico.
Ingress service and ingress look like:
xxx@c1-cp1:~/Desktop$ kubectl get svc -n ingress-...
- 113
1
vote
1
answer
714
views
How can I modify CoreDNS configmap before I bootstrap the cluster using kubeadm?
I need to build my on-prem Kubernetes cluster using kubeadm.
Since my environment has no DNS, I have to modify a configmap of CoreDNS so that it doesn't contain a forwarding section.
After deploying ...
- 393
1
vote
1
answer
1k
views
Pods on two different nodes communicate very slow, any idea why?
I am learning k8s and I have 3 nodes k8s cluster. I have just recently deployed k8s with kubeadmin and so far it is working great. everything working perfectly but the only problem that I am facing is ...
- 35
1
vote
1
answer
841
views
HA kubernetes cluster: Accidental kubeadm reset on 1 master node, connection refused when rejoining the cluster
I have setup a kubernetes cluster with 2 master nodes (cp01 192.168.1.42, cp02 192.168.1.46) and 4 worker nodes, implemented with haproxy and keepalived running as static pods in the cluster, internal ...
- 11
1
vote
1
answer
8k
views
kubeadm init fails when I use --apiserver-advertise-address
I am Installing a standalone Kubernetes cluster (kubeadm version is 1.14) on RHEL 7.7 Operating System. I have a Load Balancer (Private LB with a private IP address) configured for my Kubernetes ...
- 11
1
vote
1
answer
990
views
Online Kubernetes (kubeadm) control plane certificate renewal
kubeadm creates certificates for the Kubernetes control plane that are valid for one year. They will be renewed on every Kubernetes upgrade. Since it is definitely a good idea to update a Kubernetes ...
- 285
1
vote
1
answer
4k
views
kube-apiserver high much ram usage
I have a Kubernetes cluster with 4 nodes and around 100 pods and kube-apiserver start with flag --target-ram-mb=512
kube-apiserver consumes ~3GB of RAM and it is growing
(pprof) top
Showing nodes ...
- 11
1
vote
0
answers
24
views
Bad gateway return with k8s traefik ingress when firewalld is enable
Here is the definition of my problem.
I have a single node kubeadm cluster running on fedora cloud 40 VMs with vagrant.
I activated firewalld with this configuration:
kubernetes
sources: 10.0.0.0/8 ...
- 11
1
vote
0
answers
33
views
Failed to start ContainerManager open /proc/sys/kernel/panic: permission denied
I tryed to set up a Cubernetes Cluster on a STRATO vServer.
Every time execute kubeadm init ... kubelet crashs with the Message
"Failed to start ContainerManager open /proc/sys/kernel/panic: ...
1
vote
0
answers
66
views
Can I change controlPlaneEndpoint after kubernetes initialization?
I'm new to kubernetes and this is my kubernetes version info
kubeadm version: &version.Info{
Major:"1",
Minor:"27",
GitVersion:"v1.27.3",
GitCommit:"...
- 11
1
vote
0
answers
175
views
How to initialize kubeadm in a non-default network interface?
I have been trying to set-up Kubernetes in my university server which has two network interface. The default interface (10...*) is connected to my university network and there is another interface (...
- 111
1
vote
2
answers
3k
views
Kubeadm and kubectl - connection refused
I deployed a basic cluster on two virtual machines (kvm) with one being designated as master with control plane on it using kubeadm init - everything sees to be starting correctly, but when I try to ...
- 154
1
vote
0
answers
393
views
Dual Stack Kubernetes cluster assigning single stack IPs to pods & services
I am creating a dual stack Kubernetes cluster with kubeadm, and installing Calico. I am using the below configuration file for kubeadm:
apiVersion: kubeadm.k8s.io/v1beta3
kind: InitConfiguration
...
- 11
1
vote
1
answer
67
views
kubeadm has a empty token list
I'm running a k8s cluster to study and when I run kubeadm token list on the master node doesn't do anything, just jump to another line. And there is no file /etc/kubernetes/pki/tokens.csv on the ...
- 23