# How to initialize kubernetes cluster **URL:** \ **Category:** General Discussions\ **Created:** [May 5, 2022, 12:24pm UTC](https://discuss.kubernetes.io/t/how-to-initialize-kubernetes-cluster/19901 "2022-05-05T12:24:05Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![Vinay\_Kumar](https://sea2.discourse-cdn.com/flex016/user_avatar/discuss.kubernetes.io/vinay_kumar/32/10004_2.png) [@Vinay\_Kumar](https://discuss.kubernetes.io/u/Vinay_Kumar)\ **Post date:** [May 5, 2022, 12:24pm UTC](https://discuss.kubernetes.io/t/how-to-initialize-kubernetes-cluster/19901/1 "2022-05-05T12:24:05Z")
Hi I am trying to initialize kubernetes cluster in my ec2 instance(master node) using ansible script. I am getting below error 3 times, fatal: [3.15.220.116]: FAILED! =\> {“changed”: true, “cmd”: “kubeadm init --control-plane-endpoint :6443 --upload-certs --pod-network-cidr=192.168.0.0/16 --ignore-preflight-errors=NumCPU --ignore-preflight-errors=Mem --ignore-preflight-errors=FileContent–proc-sys-net-bridge-bridge-nf-call-iptables”, “delta”: “0:00:00.535499”, “end”: “2022-05-05 12:13:22.182358”, “msg”: “non-zero return code”, “rc”: 1, “start”: “2022-05-05 12:13:21.646859”, “stderr”: “\t[WARNING NumCPU]: the number of available CPUs 1 is less than the required 2\n\t[WARNING Mem]: the system RAM (964 MB) is less than the minimum 1700 MB\nerror execution phase preflight: [preflight] Some fatal errors occurred:\n\t[ERROR Port-6443]: Port 6443 is in use\n\t[ERROR Port-10259]: Port 10259 is in use\n\t[ERROR Port-10257]: Port 10257 is in use\n\t[ERROR FileAvailable–etc-kubernetes-manifests-kube-apiserver.yaml]: /etc/kubernetes/manifests/kube-apiserver.yaml already exists\n\t[ERROR FileAvailable–etc-kubernetes-manifests-kube-controller-manager.yaml]: /etc/kubernetes/manifests/kube-controller-manager.yaml already exists\n\t[ERROR FileAvailable–etc-kubernetes-manifests-kube-scheduler.yaml]: /etc/kubernetes/manifests/kube-scheduler.yaml already exists\n\t[ERROR FileAvailable–etc-kubernetes-manifests-etcd.yaml]: /etc/kubernetes/manifests/etcd.yaml already exists\n\t[ERROR Port-10250]: Port 10250 is in use\n\t[ERROR Port-2379]: Port 2379 is in use\n\t[ERROR Port-2380]: Port 2380 is in use\n\t[ERROR DirAvailable–var-lib-etcd]: /var/lib/etcd is not empty\n[preflight] If you know what you are doing, you can make a check non-fatal with `--ignore-preflight-errors=...`\nTo see the stack trace of this error execute with --v=5 or higher”, “stderr\_lines”: ["\t[WARNING NumCPU]: the number of available CPUs 1 is less than the required 2", “\t[WARNING Mem]: the system RAM (964 MB) is less than the minimum 1700 MB”, “error execution phase preflight: [preflight] Some fatal errors occurred:”, “\t[ERROR Port-6443]: Port 6443 is in use”, “\t[ERROR Port-10259]: Port 10259 is in use”, “\t[ERROR Port-10257]: Port 10257 is in use”, “\t[ERROR FileAvailable–etc-kubernetes-manifests-kube-apiserver.yaml]: /etc/kubernetes/manifests/kube-apiserver.yaml already exists”, “\t[ERROR FileAvailable–etc-kubernetes-manifests-kube-controller-manager.yaml]: /etc/kubernetes/manifests/kube-controller-manager.yaml already exists”, “\t[ERROR FileAvailable–etc-kubernetes-manifests-kube-scheduler.yaml]: /etc/kubernetes/manifests/kube-scheduler.yaml already exists”, “\t[ERROR FileAvailable–etc-kubernetes-manifests-etcd.yaml]: /etc/kubernetes/manifests/etcd.yaml already exists”, “\t[ERROR Port-10250]: Port 10250 is in use”, “\t[ERROR Port-2379]: Port 2379 is in use”, “\t[ERROR Port-2380]: Port 2380 is in use”, “\t[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”], “stdout”: “[init] Using Kubernetes version: v1.24.0\n[preflight] Running pre-flight checks”, “stdout\_lines”: [”[init] Using Kubernetes version: v1.24.0”, “[preflight] Running pre-flight checks”]} I used ansible script as below - name: Initializing Kubernetes cluster shell: kubeadm init --control-plane-endpoint :6443 --upload-certs --pod-network-cidr={{ cidr }} --ignore-preflight-errors=NumCPU --ignore-preflight-errors=Mem --ignore-preflight-errors=FileContent–proc-sys-net-bridge-bridge-nf-call-iptables register: output changed\_when: true - name: “Creating .kube directory” file: path: $HOME/.kube state: directory - name: “copy admin file” copy: remote\_src: yes src: /etc/kubernetes/admin.conf dest: $HOME/.kube/config - name: “Change owner of .kube/config” shell: “sudo chown $(id -u):$(id -g) $HOME/.kube/config” I am using cidr: “192.168.0.0/16” Can anyone plz suggest me about this issue? ---
**Author:** ![tej-singh-rana](https://sea2.discourse-cdn.com/flex016/user_avatar/discuss.kubernetes.io/tej-singh-rana/32/5921_2.png) [@tej-singh-rana](https://discuss.kubernetes.io/u/tej-singh-rana)\ **Post date:** [May 10, 2022, 5:57am UTC](https://discuss.kubernetes.io/t/how-to-initialize-kubernetes-cluster/19901/2 "2022-05-10T05:57:04Z")
> [@Vinay\_Kumar](#): > > “stderr”: “\t[WARNING NumCPU]: the number of available CPUs 1 is less than the required 2\n\t[WARNING Mem]: the system RAM (964 MB) is less than the minimum 1700 hey @Vinay_Kumar I think your instance resources are not sufficient for the k8s cluster. Choose t2.medium ---
**Author:** ![tej-singh-rana](https://sea2.discourse-cdn.com/flex016/user_avatar/discuss.kubernetes.io/tej-singh-rana/32/5921_2.png) [@tej-singh-rana](https://discuss.kubernetes.io/u/tej-singh-rana)\ **Post date:** [May 10, 2022, 5:58am UTC](https://discuss.kubernetes.io/t/how-to-initialize-kubernetes-cluster/19901/3 "2022-05-10T05:58:41Z")
Check this information before going to install the k8s cluster on ec2 instances. > **[Installing kubeadm](https://kubernetes.io/docs/setup/production-environment/tools/kubeadm/install-kubeadm/#before-you-begin)** > > This page shows how to install the kubeadm toolbox. For information on how to create a cluster with kubeadm once you have performed this installation process, see the Using kubeadm to Create a Cluster page. > Before you begin A compatible Linux host.... ---
**Author:** ![yanis\_BEL](https://sea2.discourse-cdn.com/flex016/user_avatar/discuss.kubernetes.io/yanis_bel/32/11573_2.png) [@yanis\_BEL](https://discuss.kubernetes.io/u/yanis_BEL)\ **Post date:** [January 10, 2023, 2:43am UTC](https://discuss.kubernetes.io/t/how-to-initialize-kubernetes-cluster/19901/4 "2023-01-10T02:43:36Z")
solution do this : ```auto kubectl apply -f https://github.com/weaveworks/weave/releases/download/v2.8.1/weave-daemonset-k8s.yaml ```