k3s-ansible/roles/k3s_server/tasks/main.yml

---
- name: Get k3s installed version
  ansible.builtin.command: k3s --version
  register: k3s_server_version_output
  changed_when: false
  failed_when: false

- name: Set k3s installed version
  when: not ansible_check_mode and k3s_server_version_output.rc == 0
  ansible.builtin.set_fact:
    k3s_server_installed_version: "{{ k3s_server_version_output.stdout_lines[0].split(' ')[2] }}"

- name: Construct K3s server config
  block:
    # Start with an empty config
    - name: Set empty server config
      ansible.builtin.set_fact:
        k3s_server_config: {}

    - name: Create k3s config directory
      ansible.builtin.file:
        path: /etc/rancher/k3s
        state: directory
        mode: '0755'

    # If token is provided, add it to the config
    - name: Add token to server config
      when: token is defined
      ansible.builtin.set_fact:
        k3s_server_config: "{{ k3s_server_config | combine({'token': token}) }}"

    - name: Determine if tls-san is already in config or args
      # noqa var-naming[no-role-prefix]
      ansible.builtin.set_fact:
        _api_endpoint_in_config: >-
          {% if server_config_yaml is defined and api_endpoint is defined and server_config_yaml | regex_search('tls-san:.*' + api_endpoint | regex_escape(), ignorecase=True) %}
          true
          {% else %}
          false
          {% endif %}
        _api_endpoint_in_args: >-
          {% if api_endpoint is defined and extra_server_args | regex_search('--tls-san[=\s]+' + api_endpoint | regex_escape(), ignorecase=True) %}
          true
          {% else %}
          false
          {% endif %}

    - name: Add TLS SAN to config if needed
      when:
        - api_endpoint is defined
        - api_endpoint != ansible_facts['hostname']
        - not (_api_endpoint_in_config | trim | bool)
        - not (_api_endpoint_in_args | trim | bool)
      ansible.builtin.set_fact:
        k3s_server_config: "{{ k3s_server_config | combine({'tls-san': api_endpoint}) }}"

    - name: Add cluster-init to server config for first server in HA-IC setup
      when:
        - (groups[server_group] | length) > 1
        - inventory_hostname == groups[server_group][0] or ansible_host == groups[server_group][0]
        - not use_external_database
      ansible.builtin.set_fact:
        k3s_server_config: "{{ k3s_server_config | combine({'cluster-init': true}) }}"

    # If not the first server in an HA-IC setup, setup the server: URL for joining the cluster
    # server: https://{{ api_endpoint }}:{{ api_port }}
    - name: Add server URL to server config for joining servers in HA-IC setup
      when: (groups[server_group] | length) > 1 and inventory_hostname != groups[server_group][0] and not use_external_database
      ansible.builtin.set_fact:
        k3s_server_config: "{{ k3s_server_config | combine({'server': 'https://' + (api_endpoint | ansible.utils.ipwrap) + ':' + api_port | string}) }}"

    # If the user has provided additional server config, merge it with the generated config
    - name: Merge user server config with generated server config
      when: server_config_yaml is defined
      ansible.builtin.set_fact:
        k3s_server_config: "{{ k3s_server_config | combine(server_config_yaml | from_yaml) }}"

# If airgapped, all K3s artifacts are already on the node.
# We should be downloading and installing the newer version only if we are in one of the following cases :
#   - we couldn't get k3s installed version in the first task of this role
#   - the installed version of K3s on the nodes is older than the requested version in ansible vars
- name: Download artifact only if needed
  when:
    - not ansible_check_mode
    - airgap_dir is undefined
    - ( k3s_server_version_output.rc != 0 or k3s_server_installed_version is version(k3s_version, '<') )
  block:
    - name: Download K3s install script
      ansible.builtin.get_url:
        url: https://get.k3s.io/
        timeout: 120
        dest: /usr/local/bin/k3s-install.sh
        owner: root
        group: root
        mode: "0755"

    - name: Set skip_download var for install script
      # noqa var-naming[no-role-prefix]
      ansible.builtin.set_fact:
        skip_download: "false"

# We always run the install script, but we skip the download step as needed
- name: Run K3s install script
  when: not ansible_check_mode
  # For some reason, ansible-lint thinks using enviroment with command is an error
  # even though its valid https://ansible.readthedocs.io/projects/lint/rules/inline-env-var/#correct-code
  ansible.builtin.command: # noqa inline-env-var
    cmd: /usr/local/bin/k3s-install.sh
  # Ensures that extra_install_envs are combined with required env vars
  environment: "{{ _install_envs }}"
  vars:
    _base_envs:
      INSTALL_K3S_SKIP_DOWNLOAD: "{{ skip_download | default('true') }}"
      INSTALL_K3S_SKIP_START: "true"
      INSTALL_K3S_VERSION: "{{ k3s_version }}"
      INSTALL_K3S_EXEC: "{{ extra_server_args }}"
    # We overrides the extra_install_envs with required keys from _base_envs on purpose
    _install_envs: "{{ extra_install_envs | default({}) | combine(_base_envs) }}"
  changed_when: true

- name: Check if user bashrc exists
  when: ansible_user is defined
  ansible.builtin.stat:
    path: "~{{ ansible_user }}/.bashrc"
  register: k3s_server_bashrc

- name: Add K3s autocomplete to user bashrc
  when:
    - ansible_user is defined
    - k3s_server_bashrc.stat.exists
  ansible.builtin.lineinfile:
    path: "~{{ ansible_user }}/.bashrc"
    regexp: '\.\s+<\(k3s completion bash\)'
    line: ". <(k3s completion bash)  # Added by k3s-ansible"

- name: Set k3s server environment file based on init system
  ansible.builtin.set_fact:
    k3s_server_env_file: "{{ (ansible_facts['service_mgr'] == 'systemd') | ternary(systemd_dir ~ '/k3s.service.env', '/etc/rancher/k3s/k3s.env') }}"

- name: Add service environment variables
  when: extra_service_envs is defined
  ansible.builtin.lineinfile:
    path: "{{ k3s_server_env_file }}"
    line: "{{ item }}"
  loop: "{{ extra_service_envs }}"

- name: Init first server node
  when: inventory_hostname == groups[server_group][0] or ansible_host == groups[server_group][0]
  block:
    - name: Convert server config to YAML and write to file
      when: not ansible_check_mode
      ansible.builtin.copy:
        content: "{{ k3s_server_config | to_nice_yaml }}"
        dest: "/etc/rancher/k3s/config.yaml"
        mode: "{{ k3s_server_config_mode }}"
      register: k3s_server_config_result

    - name: Delete any existing token from the environment if different from the new one
      ansible.builtin.lineinfile:
        state: absent
        path: "{{ k3s_server_env_file }}"
        regexp: "^K3S_TOKEN=\\s*(?!{{ token | default('') | regex_escape }}\\s*$)"

    - name: Reload systemd daemon
      when:
        - not ansible_check_mode
        - ansible_facts['service_mgr'] == 'systemd'
      ansible.builtin.systemd:
        daemon_reload: true

    - name: Enable and start K3s service
      when: not ansible_check_mode
      ansible.builtin.service:
        name: k3s
        state: restarted
        enabled: true

    - name: Pause to allow first server startup
      when: (groups[server_group] | length) > 1
      ansible.builtin.pause:
        seconds: 10

    - name: Check whether kubectl is installed on control node
      # noqa var-naming[no-role-prefix]
      ansible.builtin.command: 'kubectl'
      register: kubectl_installed
      tags: kubeconfig
      ignore_errors: true
      delegate_to: 127.0.0.1
      become: false
      changed_when: false

    # Copy the k3s config to a second file to detect changes.
    # If no changes are found, we can skip copying the kubeconfig to the control node.
    # This is dependent on the speed of the target node for k3s startup time, so retries are used.
    - name: Copy k3s.yaml to second file
      when: not ansible_check_mode
      ansible.builtin.copy:
        src: /etc/rancher/k3s/k3s.yaml
        dest: /etc/rancher/k3s/k3s-copy.yaml
        mode: "0600"
        remote_src: true
      retries: 3
      register: k3s_server_copy_yaml
      tags: kubeconfig

    - name: Apply K3S kubeconfig to control node
      when:
        - kubectl_installed.rc == 0 and (k3s_server_copy_yaml.changed or 'kubeconfig' in ansible_run_tags)
      block:
        - name: Copy kubeconfig to control node
          ansible.builtin.fetch:
            src: /etc/rancher/k3s/k3s.yaml
            dest: "{{ kubeconfig }}"
            flat: true

        - name: Change server address in kubeconfig on control node
          ansible.builtin.shell: |
            KUBECONFIG={{ kubeconfig }} kubectl config set-cluster default --server=https://{{ api_endpoint | ansible.utils.ipwrap }}:{{ api_port }}
          delegate_to: 127.0.0.1
          become: false
          register: k3s_server_csa_result
          changed_when:
            - k3s_server_csa_result.rc == 0

        - name: Setup kubeconfig context on control node - {{ cluster_context }}
          when: kubeconfig == "~/.kube/config.new"
          ansible.builtin.replace:
            path: "{{ kubeconfig }}"
            regexp: 'default'
            replace: '{{ cluster_context }}'
          delegate_to: 127.0.0.1
          become: false

        - name: Merge with any existing kubeconfig on control node
          when: kubeconfig == "~/.kube/config.new"
          ansible.builtin.shell: |
            TFILE=$(mktemp)
            KUBECONFIG={{ kubeconfig }}:~/.kube/config kubectl config set-context {{ cluster_context }} --user={{ cluster_context }} --cluster={{ cluster_context }}
            KUBECONFIG={{ kubeconfig }}:~/.kube/config kubectl config view --flatten > ${TFILE}
            mv ${TFILE} ~/.kube/config
          delegate_to: 127.0.0.1
          become: false
          register: k3s_server_mv_result
          changed_when:
            - k3s_server_mv_result.rc == 0

    - name: Get the token if randomly generated
      when:
        - not ansible_check_mode
        - token is not defined
      block:
        - name: Wait for token
          ansible.builtin.wait_for:
            path: /var/lib/rancher/k3s/server/token

        - name: Read node-token from first server
          ansible.builtin.slurp:
            src: /var/lib/rancher/k3s/server/token
          register: k3s_server_node_token

        - name: Store random token for later servers
          # noqa var-naming[no-role-prefix]
          ansible.builtin.set_fact:
            random_token: "{{ k3s_server_node_token.content | b64decode | regex_replace('\n', '') }}"

- name: Start other server if any and verify status
  when:
    - (groups[server_group] | length) > 1
    - inventory_hostname != groups[server_group][0] and ansible_host != groups[server_group][0]
  block:
    - name: Get token from first server if needed
      when: token is not defined and hostvars[groups[server_group][0]].random_token is defined
      # noqa var-naming[no-role-prefix]
      ansible.builtin.set_fact:
        k3s_server_config: "{{ k3s_server_config | combine({'token': hostvars[groups[server_group][0]].random_token}) }}"

    - name: Convert server config to YAML and write to file
      when: not ansible_check_mode
      ansible.builtin.copy:
        content: "{{ k3s_server_config | to_nice_yaml }}"
        dest: "/etc/rancher/k3s/config.yaml"
        mode: "{{ k3s_server_config_mode }}"
      register: k3s_server_config_result

    - name: Delete any existing token from the environment if different from the new one
      ansible.builtin.lineinfile:
        state: absent
        path: "{{ k3s_server_env_file }}"
        regexp: "^K3S_TOKEN=\\s*(?!{{ token | default('') | regex_escape }}\\s*$)"

    - name: Reload systemd daemon
      when:
        - not ansible_check_mode
        - ansible_facts['service_mgr'] == 'systemd'
      ansible.builtin.systemd:
        daemon_reload: true

    # Always restart a joined server so a re-run of site.yml — whether it only
    # bumped k3s_version or changed config — brings it onto the new runtime, the
    # same way the first server above always restarts. On a multi-server cluster
    # run the playbook with --forks=1 so the servers restart one at a time and
    # the etcd quorum is preserved (see README).
    - name: Restart K3s service
      when:
        - ansible_facts.services['k3s.service'] is defined
        - ansible_facts.services['k3s.service'].state == 'running'
      ansible.builtin.service:
        name: k3s
        state: restarted

    - name: Enable and start K3s service
      when: ansible_facts.services['k3s.service'] is not defined or ansible_facts.services['k3s.service'].state != 'running'
      ansible.builtin.service:
        name: k3s
        state: started
        enabled: true

    - name: Verify that all server nodes joined
      when: not ansible_check_mode and (groups[server_group] | length) > 1
      ansible.builtin.command:
        cmd: >
          k3s kubectl get nodes -l "node-role.kubernetes.io/control-plane=true" -o=jsonpath="{.items[*].metadata.name}"
      register: k3s_server_nodes
      until: k3s_server_nodes.rc == 0 and (k3s_server_nodes.stdout.split() | length) == (groups[server_group] | length)
      retries: 20
      delay: 10
      changed_when: false

- name: Wait for control plane to be ready
  ansible.builtin.wait_for:
    host: "{{ api_endpoint }}"
    port: "{{ api_port }}"
    timeout: 60
  run_once: true
  changed_when: false

- name: Setup kubectl for user
  when: user_kubectl
  block:
    - name: Create directory .kube
      ansible.builtin.file:
        path: ~{{ ansible_user }}/.kube
        state: directory
        owner: "{{ ansible_user }}"
        mode: "u=rwx,g=rx,o="

    - name: Copy config file to user home directory
      when: not ansible_check_mode
      ansible.builtin.copy:
        src: /etc/rancher/k3s/k3s.yaml
        dest: ~{{ ansible_user }}/.kube/config
        remote_src: true
        owner: "{{ ansible_user }}"
        mode: "u=rw,g=,o="

    - name: Configure default KUBECONFIG for user
      when: k3s_server_bashrc.stat.exists
      ansible.builtin.lineinfile:
        path: ~{{ ansible_user }}/.bashrc
        regexp: 'export KUBECONFIG=~/.kube/config'
        line: 'export KUBECONFIG=~/.kube/config # Added by k3s-ansible'
        state: present

    - name: Configure kubectl autocomplete
      when: k3s_server_bashrc.stat.exists
      ansible.builtin.lineinfile:
        path: ~{{ ansible_user }}/.bashrc
        regexp: '\.\s+<\(kubectl completion bash\)'
        line: ". <(kubectl completion bash)  # Added by k3s-ansible"