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Can you help me debug the master initialization?

I get the error timed out waiting for the condition when I try to initialize the master:

[email protected]:~# kubeadm init --config=kubeadm-config.yaml --upload-certs | tee kubeadm-init.out
W0103 15:13:11.353300    8986 configset.go:202] WARNING: kubeadm cannot validate component configs for API groups [kubelet.config.k8s.io kubeproxy.config.k8s.io]
[init] Using Kubernetes version: v1.18.1
[preflight] Running pre-flight checks
    [WARNING Service-Docker]: docker service is not enabled, please run 'systemctl enable docker.service'
    [WARNING IsDockerSystemdCheck]: detected "cgroupfs" as the Docker cgroup driver. The recommended driver is "systemd". Please follow the guide at https://kubernetes.io/docs/setup/cri/
[preflight] Pulling images required for setting up a Kubernetes cluster
[preflight] This might take a minute or two, depending on the speed of your internet connection
[preflight] You can also perform this action in beforehand using 'kubeadm config images pull'
[kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[kubelet-start] Starting the kubelet
[certs] Using certificateDir folder "/etc/kubernetes/pki"
[certs] Generating "ca" certificate and key
[certs] Generating "apiserver" certificate and key
[certs] apiserver serving cert is signed for DNS names [master kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local k8smaster] and IPs [10.96.0.1 10.2.0.2]
[certs] Generating "apiserver-kubelet-client" certificate and key
[certs] Generating "front-proxy-ca" certificate and key
[certs] Generating "front-proxy-client" certificate and key
[certs] Generating "etcd/ca" certificate and key
[certs] Generating "etcd/server" certificate and key
[certs] etcd/server serving cert is signed for DNS names [master localhost] and IPs [10.2.0.2 127.0.0.1 ::1]
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [master localhost] and IPs [10.2.0.2 127.0.0.1 ::1]
[certs] Generating "etcd/healthcheck-client" certificate and key
[certs] Generating "apiserver-etcd-client" certificate and key
[certs] Generating "sa" key and public key
[kubeconfig] Using kubeconfig folder "/etc/kubernetes"
[kubeconfig] Writing "admin.conf" kubeconfig file
[kubeconfig] Writing "kubelet.conf" kubeconfig file
[kubeconfig] Writing "controller-manager.conf" kubeconfig file
[kubeconfig] Writing "scheduler.conf" kubeconfig file
[control-plane] Using manifest folder "/etc/kubernetes/manifests"
[control-plane] Creating static Pod manifest for "kube-apiserver"
[control-plane] Creating static Pod manifest for "kube-controller-manager"
W0103 15:13:33.458024    8986 manifests.go:225] the default kube-apiserver authorization-mode is "Node,RBAC"; using "Node,RBAC"
[control-plane] Creating static Pod manifest for "kube-scheduler"
W0103 15:13:33.459355    8986 manifests.go:225] the default kube-apiserver authorization-mode is "Node,RBAC"; using "Node,RBAC"
[etcd] Creating static Pod manifest for local etcd in "/etc/kubernetes/manifests"
[wait-control-plane] Waiting for the kubelet to boot up the control plane as static Pods from directory "/etc/kubernetes/manifests". This can take up to 4m0s
[kubelet-check] Initial timeout of 40s passed.
[kubelet-check] 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 error: Get http://localhost:10248/healthz: dial tcp 127.0.0.1:10248: connect: connection refused.
[kubelet-check] 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 error: Get http://localhost:10248/healthz: dial tcp 127.0.0.1:10248: connect: connection refused.

    Unfortunately, an error has occurred:
        timed out waiting for the condition

    This error is likely caused by:
        - The kubelet is not running
        - The kubelet is unhealthy due to a misconfiguration of the node in some way (required cgroups disabled)

    If you are on a systemd-powered system, you can try to troubleshoot the error with the following commands:
        - 'systemctl status kubelet'
        - 'journalctl -xeu kubelet'

    Additionally, a control plane component may have crashed or exited when started by the container runtime.
    To troubleshoot, list all containers using your preferred container runtimes CLI.

    Here is one example how you may list all Kubernetes containers running in docker:
        - 'docker ps -a | grep kube | grep -v pause'
        Once you have found the failing container, you can inspect its logs with:
        - 'docker logs CONTAINERID'

error execution phase wait-control-plane: couldn't initialize a Kubernetes cluster
To see the stack trace of this error execute with --v=5 or higher

Answers

  • serewicz
    serewicz Posts: 942

    Hello,

    That errors include localhost and not the k8smaster alias indicate an issue with the location of the kubeadm-config.yaml file, the syntax of the file, and/or the edit to /etc/hosts.

    As it seems you have deviated from the labs as written I would encourage you to slow down and read, and follow, each step carefully. After you get a cluster working you can revisit, experiment, and diverge from the labs.

    Regards,

  • alaudazzi
    alaudazzi Posts: 19

    I've been following the steps in the lab very carefully, without deviating in any way. It's not clear to me what went wrong. I would really appreciate some help to move forward. I am currently blocked and cannot continue with the course.

  • serewicz
    serewicz Posts: 942

    Hello,

    As I look through your previous questions and examples it is clear you are not following the exercise guide.

    Let's start with some ground work. We can go step by step to get you back on track. What are you using for you nodes, GCE, AWS, Virtual Box?

  • alaudazzi
    alaudazzi Posts: 19

    GCE

  • alaudazzi
    alaudazzi Posts: 19

    I've just fixed a typo in the file /etc/hosts and rerun kubeadm init --config=kubeadm-config.yaml --upload-certs | tee kubeadm-init.out
    Now I get this:

    [email protected]:~# kubeadm init --config=kubeadm-config.yaml --upload-certs | tee kubeadm-init.out
    W0103 20:06:49.751110   19618 configset.go:202] WARNING: kubeadm cannot validate component configs for API groups [kubelet.config.k8s.io kubeproxy.config.k8s.io]
    [init] Using Kubernetes version: v1.18.1
    [preflight] Running pre-flight checks
        [WARNING Service-Docker]: docker service is not enabled, please run 'systemctl enable docker.service'
        [WARNING IsDockerSystemdCheck]: detected "cgroupfs" as the Docker cgroup driver. The recommended driver is "systemd". Please follow the guide at https://kubernetes.io/docs/setup/cri/
    error execution phase preflight: [preflight] Some fatal errors occurred:
        [ERROR Port-6443]: Port 6443 is in use
        [ERROR Port-10259]: Port 10259 is in use
        [ERROR Port-10257]: Port 10257 is in use
        [ERROR FileAvailable--etc-kubernetes-manifests-kube-apiserver.yaml]: /etc/kubernetes/manifests/kube-apiserver.yaml already exists
        [ERROR FileAvailable--etc-kubernetes-manifests-kube-controller-manager.yaml]: /etc/kubernetes/manifests/kube-controller-manager.yaml already exists
        [ERROR FileAvailable--etc-kubernetes-manifests-kube-scheduler.yaml]: /etc/kubernetes/manifests/kube-scheduler.yaml already exists
        [ERROR FileAvailable--etc-kubernetes-manifests-etcd.yaml]: /etc/kubernetes/manifests/etcd.yaml already exists
        [ERROR Port-10250]: Port 10250 is in use
        [ERROR Port-2379]: Port 2379 is in use
        [ERROR Port-2380]: Port 2380 is in use
        [ERROR DirAvailable--var-lib-etcd]: /var/lib/etcd is not empty
    [preflight] If you know what you are doing, you can make a check non-fatal with `--ignore-preflight-errors=...`
    To see the stack trace of this error execute with --v=5 or higher
    
    
  • serewicz
    serewicz Posts: 942

    Are you using cri-o or docker as the container engine? You have missed a step either way as it cannot find the docker or cri-o engine. The init process has a search order which first looks for docker then cri-o then containerd. The error says docker is not enabled. Did you run the exercise step to install docker?

    Now that I know you are using GCE, did you create a VPC which allows all traffic to all ports? Did you run step 2 and 3 of the exercise?

  • alaudazzi
    alaudazzi Posts: 19

    Docker is correctly installed:

    [email protected]:~# docker -v
    Docker version 19.03.6, build 369ce74a3c
    
  • serewicz
    serewicz Posts: 942

    What is the output of sudo systemctl status docker?

    Can you write your command history to a file and share it? history > history.out

  • alaudazzi
    alaudazzi Posts: 19

    The VPC I created should allow all traffic to all ports:

  • serewicz
    serewicz Posts: 942

    Great, the VPC looks good. What size nodes are you using, and what version on Ubuntu?

  • alaudazzi
    alaudazzi Posts: 19

    n1-standard-2 (2 vCPUs, 7.5 GB memory) with Ubuntu, 18.04 LTS

  • alaudazzi
    alaudazzi Posts: 19

    This is the output of sudo systemctl status docker:

    [email protected]:~# sudo systemctl status docker
    ● docker.service - Docker Application Container Engine
       Loaded: loaded (/lib/systemd/system/docker.service; disabled; vendor preset: enabled)
       Active: active (running) since Sun 2021-01-03 15:13:12 UTC; 6h ago
         Docs: https://docs.docker.com
     Main PID: 9004 (dockerd)
        Tasks: 17
       CGroup: /system.slice/docker.service
               └─9004 /usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock
    [email protected]:~# 
    
  • serewicz
    serewicz Posts: 942

    That looks right as well. Could you show the commands and put up to the point of kubeadm init please.

  • alaudazzi
    alaudazzi Posts: 19

    Here is the most recent command history:

    [email protected]:~# history
        1  apt-get update && apt-get upgrade -y
        2  apt-get install -y vim
        3  vim
        4  apt-get install -y docker.io
        5  pwd
        6  ls
        7  vim /etc/apt/source.list.d/kubernetes.list
        8  vim /etc/apt/sources.list.d/kubernetes.list
        9  curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | apt-key add -
       10  pwd
       11  ls
       12  apt-get update
       13  apt-get install -y kubeadm=1.18.1-00 kubelet=1.18.1-00 kubectl=1.18.1-00
       14  apt-mark hold kubelet kubeadm kubectl
       15  wget https://docs.projectcalico.org/manifests/calico.yaml
       16  less
       17  less calico.yaml
       18  ip addr show
       19  vim /etc/hosts
       20  vim kubeadm-config.yaml
       21  kubeadm init --config=kubeadm-config.yaml --upload-certs | tee kubeadm-init.out
       22  less calico.yaml
       23  kubeadm init --config=kubeadm-config.yaml --upload-certs | tee kubeadm-init.out
       24  vi kubeadm-init.out
       25  docker ps -a | grep kube | grep -v pause
       26  systemctl status kubelet
       27  journalctl -xeu kubelet
       28  vim /etc/hosts
       29  apt-get update
       30  less calico.yaml
       31  ip addr show
       32  vim /etc/hosts
       33  vim kubeadm-config.yaml 
       34  kubeadm init --config=kubeadm-config.yaml --upload-certs | tee kubeadm-init.out
       35  wget https://docs.projectcalico.org/manifests/calico.yaml
       36  less calico.yaml
       37  kubeadm init --config=kubeadm-config.yaml --upload-certs | tee kubeadm-init.out
       38  docker ps
       39  docker -v
       40  sudo systemctl status docker
       41  history > history.out
       42  history
    [email protected]:~#
    
  • alaudazzi
    alaudazzi Posts: 19

    I fixed the problem by running kubeadm reset.

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