Simple Ansible playbook to install Fail2ban.

fail2ban-playbook.yml

--- 
- name: installs fail2ban on ansible hosts
  hosts: fail2ban-hosts
  become: yes
  tasks:
  
  - name: install apt fail2ban packages
    apt: 
      name: "{{ item }}"   
      state: latest
      update_cache: yes
      cache_valid_time: 3600
    with_items:
      - fail2ban
      - sendmail
  
  - name: override the basic fail2ban configuration with .local file
    copy:
      src: jail.local
      dest: /etc/fail2ban/jail.local
      owner: root
      group: root
      mode: 0644

Needs to be accompanied by jail.local template file e.g. https://gist.github.com/5car1z/9c143fd17e61d074ec95207380ba9969

https://www.tricksofthetrades.net/2018/05/19/ansible-fail2ban-playbook/