Ansible Playbook Examples

The job platform supports Ansible Playbooks for batch execution of day-to-day operational work.

A Playbook must contain:

• hosts: the target hosts to run against
• tasks: the list of tasks to execute
• tasks consists of individual tasks, and each task can use a different Ansible module.

---
- name: Update web servers
  hosts: webservers
  remote_user: root

  tasks:
  - name: Ensure apache is at the latest version
    ansible.builtin.yum:
      name: httpd
      state: latest
  - name: Write the apache config file
    ansible.builtin.template:
      src: /srv/httpd.j2
      dest: /etc/httpd.conf

- name: Update db servers
  hosts: databases
  remote_user: root

  tasks:
  - name: Ensure postgresql is at the latest version
    ansible.builtin.yum:
      name: postgresql
      state: latest
  - name: Ensure that postgresql is started
    ansible.builtin.service:
      name: postgresql
      state: started

1. Installing software

- name: Install a list of packages
  yum:
    name:
      - nginx
      - postgresql
      - postgresql-server
    state: present

- name: Download the nginx package but do not install it
  yum:
    name:
      - nginx
    state: latest
    download_only: true

1. Managing configuration templates

- name: Update sshd configuration safely, avoid locking yourself out
  template:
    src: etc/ssh/sshd_config.j2
    dest: /etc/ssh/sshd_config
    owner: root
    group: root
    mode: '0600'
    validate: /usr/sbin/sshd -t -f %s
    backup: yes

1. Managing services

- name: Start service httpd, if not started
  service:
    name: httpd
    state: started

- name: Stop service httpd, if started
  service:
    name: httpd
    state: stopped

- name: Restart service httpd, in all cases
  service:
    name: httpd
    state: restarted

- name: Reload service httpd, in all cases
  service:
    name: httpd
    state: reloaded

- name: Enable service httpd, and not touch the state
  service:
    name: httpd
    enabled: yes

Handlers

---
- name: Verify apache installation
  hosts: webservers
  vars:
    http_port: 80
    max_clients: 200
  remote_user: root
  tasks:
    - name: Ensure apache is at the latest version
      ansible.builtin.yum:
        name: httpd
        state: latest

    - name: Write the apache config file
      ansible.builtin.template:
        src: /srv/httpd.j2
        dest: /etc/httpd.conf
      notify:
        - Restart apache

    - name: Ensure apache is running
      ansible.builtin.service:
        name: httpd
        state: started

  handlers:
    - name: Restart apache
      ansible.builtin.service:
        name: httpd
        state: restarted