DevOps Classroom Notes – 14/July/2024

Ansible contd

Writing one playbook for multiple distributions

• We have discussed the apache server installation
• Playbook is as shown below

---
- name: install apache
  hosts: webservers
  become: yes
  tasks:
    - name: check if playbook is executed on supported distribution
      ansible.builtin.fail:
        msg: "This playbook is designed to run only on ubuntu and redhat"
      when: ansible_facts['distribution'] != 'Ubuntu'  and ansible_facts['distribution'] != 'RedHat'
    - name: update and install apache2
      ansible.builtin.package:
        name: "{{ package_name }}"
        state: present
    - name: enable and start apache
      ansible.builtin.systemd:
        name: "{{ package_name }}"
        enabled: yes
        state: started
   

Ansible roles

• Roles are reusable ansible assets (playbooks)
• From playbooks we can call roles
• Ansible galaxy has a huge collection of roles Refer Here
• Now lets try using ansible role for install apache Refer Here
• Now lets view the role Refer Here
• Refer Here for the changes
• Refer Here for the changes to create a role (we have created a role from tomcat playbook)

Ansible Collections

• Ansible has two reusable assets
  • role
  • module
• if organizations are building custom modules Refer Here
• To solve this problem ansible has introduced the concept of collections.
• An ansible collection is combination of
  • roles
  • custom modules

Ansible Vault

• Vaults are used to encrypt sensitive content
• Refer Here for official docs
• vaults can be encrypted and decrypted with
  • secret text
  • secret file

Ansible parallelism

• Ansible can parallely execute on 5 systems by default and this can be changed with forks
• Refer Here