Role info

This playbook is not for fully setting up a Kubernetes Cluster.

It only helps you automate the standard Kubernetes bootstrapping pre-reqs.

Supported OS

• Ubuntu 24.04
• Ubuntu 22.04
• Ubuntu 20.04
• Ubuntu 18.04

Required Ansible

Ansible version required 2.10+

Tasks in the role

This role contains tasks to:

• Install basic packages required
• Setup standard system requirements - Disable Swap, Modify sysctl, Disable SELinux
• Install and configure a container runtime of your Choice - cri-o, Docker, Containerd
• Install the Kubernetes packages - kubelet, kubeadm and kubectl

How to use this role

• Clone the Project:

$ git clone https://github.com/cloudspinx/k8s-bootstrap.git

• Configure /etc/hosts file in your bastion or workstation with all nodes and ip addresses. Example:

192.168.200.10 k8smaster01.example.com k8smaster01
192.168.200.11 k8smaster02.example.com k8smaster02
192.168.200.12 k8smaster03.example.com k8smaster03
192.168.200.13 k8snode01.example.com k8snode01
192.168.200.14 k8snode02.example.com k8snode02
192.168.200.15 k8snode03.example.com k8snode03
192.168.200.16 k8snode04.example.com k8snode04

• Update your inventory, for example:

$ vim hosts
[k8snodes]
k8smaster01
k8smaster02
k8smaster03
k8snode01
k8snode02
k8snode03
k8snode04

• Update variables in playbook file

$ vim k8s-prep.yml
---
- name: Prepare Kubernetes Nodes for Cluster bootstrappinghosts: k8snodesremote_user: rootbecome: yesbecome_method: sudo#gather_facts: novars:
k8s_version: "1.32"# Kubernetes version to be installedtimezone: "UTC"# Timezone to set on all nodesk8s_cni: calico # calico, flannelcontainer_runtime: cri-o # docker, cri-o, containerd pod_network_cidr: "172.18.0.0/16"# pod subnet if using cri-o runtime# Docker proxy supportsetup_proxy: false # Set to true to configure proxyproxy_server: "proxy.example.com:8080"# Proxy server address and portdocker_proxy_exclude: "localhost,127.0.0.1"# Adresses to exclude from proxyroles:
- kubernetes-bootstrap

If you are using non root remote user, then set username and enable sudo:

become: yes
become_method: sudo

To enable proxy, set the value of setup_proxy to true and provide proxy details.

Running Playbook

Once all values are updated, you can then run the playbook against your nodes.

NOTE: Recommended to disable. if you must enable, a pattern in hostname is required for master and worker nodes:

Check playbook syntax to ensure no errors:

$ ansible-playbook --syntax-check k8s-prep.yml -i hosts
playbook: k8s-prep.yml

Playbook executed as root user - with ssh key:

$ ansible-playbook -i hosts k8s-prep.yml

Playbook executed as root user - with password:

$ ansible-playbook -i hosts k8s-prep.yml --ask-pass

Playbook executed as sudo user - with password:

$ ansible-playbook -i hosts k8s-prep.yml --ask-pass --ask-become-pass

Playbook executed as sudo user - with ssh key and sudo password:

$ ansible-playbook -i hosts k8s-prep.yml --ask-become-pass

Playbook executed as sudo user - with ssh key and passwordless sudo:

$ ansible-playbook -i hosts k8s-prep.yml --ask-become-pass

Execution should be successful without errors:

TASK [kubernetes-bootstrap : Reload firewalld] *********************************************************************************************************
changed: [k8smaster01]
changed: [k8snode01]
changed: [k8snode02]
PLAY RECAP *********************************************************************************************************************************************
k8smaster01 : ok=23 changed=3 unreachable=0 failed=0 skipped=11 rescued=0 ignored=0
k8snode01 : ok=23 changed=3 unreachable=0 failed=0 skipped=11 rescued=0 ignored=0
k8snode02 : ok=23 changed=3 unreachable=0 failed=0 skipped=11 rescued=0 ignored=0

Next check article on bootsrapping k8s control plane: https://computingforgeeks.com/how-to-install-kubernetes-on-ubuntu-complete-steps/