cluster/k3s/ansible/create-cluster.yml

---
- name: Gather IPv4 address facts for all hosts
  hosts: all
  gather_facts: yes
  vars:
    dns_server: "192.168.1.151"
  tasks:
    - name: Configure systemd-resolved to use custom DNS
      become: true
      copy:
        dest: /etc/systemd/resolved.conf
        content: |
          [Resolve]
          DNS={{ dns_server }}
          FallbackDNS=192.168.1.1
          Domains=mngoma.lab
          DNSStubListener=yes
        owner: root
        group: root
        mode: "0644"

    - name: Ensure systemd-resolved service is enabled and restarted
      become: true
      systemd:
        name: systemd-resolved
        state: restarted
        enabled: yes
        
    - name: Ensure host IPv4 address is available and stored as fact
      set_fact:
        node_ipv4: "{{ ansible_default_ipv4.address }}"
      when: ansible_default_ipv4 is defined and ansible_default_ipv4.address is defined

    - name: Fail if IPv4 address could not be determined
      fail:
        msg: "Could not determine IPv4 address for {{ inventory_hostname }}. Please check network configuration."
      when: node_ipv4 is not defined
      
    - name: Ensure /home/{{ ansible_user }}/k3s directory exists
      become: yes
      file:
        path: /home/{{ ansible_user }}/k3s
        state: directory
        owner: root
        group: root
        mode: '0777'

- name: Initialise the K3s control plane (manager)
  hosts: manager
  become: yes
  vars:
    k3s_version: v1.29.4+k3s1
    kubeconfig_dir: "/home/{{ ansible_user }}/.kube"
    kubeconfig_file: "{{ kubeconfig_dir }}/config"
  tasks:
    - name: Install required apt dependencies
      apt:
        name:
          - curl
          - python3-pip
          - python3-venv
        state: present
        update_cache: yes

    - name: Create a Python virtual environment for Ansible k8s modules
      command: python3 -m venv /opt/ansible-venv
      args:
        creates: /opt/ansible-venv

    - name: Install Kubernetes and OpenShift libraries in the venv
      command: /opt/ansible-venv/bin/pip install kubernetes openshift

    - name: Install k3s on manager (control plane)
      shell: |
        curl -sfL https://get.k3s.io | INSTALL_K3S_VERSION={{ k3s_version }} sh -
      args:
        creates: /usr/local/bin/k3s

    - name: Gather architecture for kubectl
      set_fact:
        kubectl_arch: |
          {% if ansible_architecture == "x86_64" %}
          amd64
          {% elif "armv7l" in ansible_architecture %}
          arm
          {% elif "aarch64" in ansible_architecture %}
          arm64
          {% else %}
          {{ ansible_architecture }}
          {% endif %}

    - name: Download latest kubectl binary
      shell: |
        curl -Lo /usr/local/bin/kubectl "https://dl.k8s.io/release/$(curl -L -s https://dl.k8s.io/release/stable.txt)/bin/linux/{{ kubectl_arch }}/kubectl"
      args:
        creates: /usr/local/bin/kubectl

    - name: Make kubectl executable
      file:
        path: /usr/local/bin/kubectl
        mode: '0755'
        owner: root
        group: root

    - name: Validate kubectl version
      shell: kubectl version --client --output=yaml
      register: kubectl_version
      changed_when: false

    - name: Show kubectl version
      debug:
        var: kubectl_version.stdout

    - name: Ensure .kube directory exists for ansible user
      become_user: "{{ ansible_user }}"
      file:
        path: "{{ kubeconfig_dir }}"
        state: directory
        owner: "{{ ansible_user }}"
        group: "{{ ansible_user }}"
        mode: '0700'

    - name: Copy kubeconfig file to ansible user home
      become: true
      copy:
        src: /etc/rancher/k3s/k3s.yaml
        dest: "{{ kubeconfig_file }}"
        owner: "{{ ansible_user }}"
        group: "{{ ansible_user }}"
        mode: '0600'
        remote_src: yes

    - name: Replace server IP in kubeconfig with manager's IP address
      become_user: "{{ ansible_user }}"
      lineinfile:
        path: "{{ kubeconfig_file }}"
        regexp: 'server: https://127\\.0\\.0\\.1:6443'
        line: "    server: https://{{ node_ipv4 }}:6443"

    - name: Get the cluster join token
      shell: cat /var/lib/rancher/k3s/server/node-token
      register: k3s_token
      changed_when: false

    - name: Set fact for join token and manager IP
      set_fact:
        k3s_node_token: "{{ k3s_token.stdout }}"
        manager_ip: "{{ node_ipv4 }}"

    - name: Add the join token and manager IP to hostvars for workers
      add_host:
        name: "cluster_primary"
        groups: join_info
        k3s_node_token: "{{ k3s_node_token }}"
        k3s_manager_ip: "{{ manager_ip }}"

- name: Install and join worker nodes to the control plane
  hosts: workers
  become: yes
  vars:
    k3s_version: v1.29.4+k3s1
  tasks:
    - name: Install required dependencies
      apt:
        name: [curl]
        state: present
        update_cache: yes

    - name: Ensure /home/{{ ansible_user }}/k3s directory exists
      file:
        path: /home/{{ ansible_user }}/k3s
        state: directory
        owner: root
        group: root
        mode: '0777'

    - name: Set manager join information
      set_fact:
        k3s_node_token: "{{ hostvars[groups['join_info'][0]]['k3s_node_token'] }}"
        k3s_manager_ip: "{{ hostvars[groups['join_info'][0]]['k3s_manager_ip'] }}"

    - name: Fail if manager's IP is not available
      fail:
        msg: "Could not determine manager's IP for joining cluster!"
      when: k3s_manager_ip is not defined

    - name: Install k3s agent (worker)
      shell: |
        curl -sfL https://get.k3s.io | K3S_URL=https://{{ k3s_manager_ip }}:6443 K3S_TOKEN={{ k3s_node_token }} INSTALL_K3S_VERSION={{ k3s_version }} sh -
      args:
        creates: /usr/local/bin/k3s-agent

    - name: Gather architecture for kubectl
      set_fact:
        kubectl_arch: |
          {% if ansible_architecture == "x86_64" %}
          amd64
          {% elif "armv7l" in ansible_architecture %}
          arm
          {% elif "aarch64" in ansible_architecture %}
          arm64
          {% else %}
          {{ ansible_architecture }}
          {% endif %}

    - name: Download latest kubectl binary (worker)
      shell: |
        curl -Lo /usr/local/bin/kubectl "https://dl.k8s.io/release/$(curl -L -s https://dl.k8s.io/release/stable.txt)/bin/linux/{{ kubectl_arch }}/kubectl"
      args:
        creates: /usr/local/bin/kubectl

    - name: Make kubectl executable (worker)
      file:
        path: /usr/local/bin/kubectl
        mode: '0755'
        owner: root
        group: root

- name: Verify cluster nodes from manager node and configure storage
  hosts: manager
  become: yes
  vars:
    kubeconfig_file: "/home/{{ ansible_user }}/.kube/config"
  tasks:
    - name: Wait for all worker nodes to join the cluster
      become_user: "{{ ansible_user }}"
      shell: |
        for i in {1..10}; do
          [ $(kubectl --kubeconfig={{ kubeconfig_file }} get nodes | grep -c worker) -ge 1 ] && exit 0
          sleep 15
        done
        exit 1
      register: wait_worker
      failed_when: wait_worker.rc != 0

    - name: List all k3s nodes
      become_user: "{{ ansible_user }}"
      shell: kubectl --kubeconfig={{ kubeconfig_file }} get nodes -o wide
      register: all_nodes

    - name: Show current k3s cluster nodes
      debug:
        var: all_nodes.stdout

    - name: Create StorageClass for /home/ansible/k3s INLINE
      vars:
        ansible_python_interpreter: /opt/ansible-venv/bin/python
      kubernetes.core.k8s:
        kubeconfig: "{{ kubeconfig_file }}"
        definition:
          apiVersion: storage.k8s.io/v1
          kind: StorageClass
          metadata:
            name: local-pvs
          provisioner: kubernetes.io/no-provisioner
          volumeBindingMode: WaitForFirstConsumer