DevOps Classroom Series – 20/Mar/2020

Ansible Galaxy

• Repository of Reusable Ansible Artifacts
• Lets do a simple expermient of installing of installing nodejs using ansible-galaxy reusable assets.
• Reusability is provided by Ansible Roles.
• Now navigate to ansible galaxy and search for node js and select any role
• Install role using ansible-galaxy command

ansible-galaxy install geerlingguy.nodejs

• Now write a simple playbook to use this role

---
- hosts: all
  become: yes
  roles:
    - geerlingguy.nodejs

• Now run this playbook

ansible-playbook node.yaml --syntax-check
ansible-playbook node.yaml

• Now verify whether the node is installed or not

node --version
npm --version

• DevOps Responsibilities:
  • You should know how to use community roles (ansible-galaxy)
  • You should know how to create custom roles

Reusable Assests in Ansible

• Refer Here for the official documentation
• Experiment:
  • Write a playbook to install git, nano and tree

  ---
  - hosts: all
  become: yes
  vars:
      packages:
      - git
      - tree
      - nano
      - elinks
  tasks:
      - name: install packages
      package:
          name: "{{ item }}"
          state: present
      loop: "{{ packages }}"
  

  • Write a playbook to install apache2

  ---
  - hosts: all
  become: yes
  tasks:
      - name: install apache
      package:
          name: apache2
          state: present
      notify: 
          - restart apache
  handlers:
      - name: restart apache
      service:
          name: apache2
          enabled: yes
          state: restarted
  

  • Now while installing apache, you are asked to install utilites (git, nano, tree, elinks)
  • Possible Solution 1: Use ansible-playbook to execute util.yaml and then apache.yaml
  • Possible Solution 2: Use import or include

---
- import_playbook: util.yaml
- hosts: all
  become: yes
  tasks:
    - name: install apache
      package:
        name: apache2
        state: present
      notify: 
        - restart apache
  handlers:
    - name: restart apache
      service:
        name: apache2
        enabled: yes
        state: restarted    

* Possible Solution 3: Creating a role

Ansible Roles:

• Refer Here for official docs
• Lets create a reusable role for tomcat8. The tomcat8 playbook is already created Refer Here
• Now create a tomcat8 role by using the following command

ansible-galaxy role init tomcat8

• Now try to create a ansible role for tomcat8 by copying the necessary contents in necessary yaml files.